ESO Garching Science Colloquia and Seminars 2014

January 2014

08.01.14 (Wednesday)
16:30, Cluster building, Boltzmannstr. 2, Cluster Universe Colloquium
"What really are the limits on electroweak sparticles from the LHC?"
Aoife Bharucha (TUM)
Abstract
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"What really are the limits on electroweak sparticles from the LHC?"

Aoife Bharucha (TUM)

Abstract
Supersymmetry (SUSY) is a theory providing possible solutions to many unanswered questions, such as the nature of dark matter and the hierarchy problem. However, so far none of the supersymmetric partners of the standard model particles (sparticles), predicted by this theory have been seen at colliders. The LHC in particular has been successful in pushing the limits on these sparticles towards the TeV scale, particularly for coloured sparticles. The production of electroweak sparticles is suppressed, and therefore the bounds are much weaker. The LHC experiments interpret their results in terms of simplified models, and the severity of the resulting bounds has resulted in people questioning whether SUSY can really still answer the hierarchy problem. Aoife will present what the bounds on these particles really are, particularly for the case of electroweak sparticles, the lightest of which is a potential candidate for WIMP-like dark matter. Further, Aoife will discuss whether, in the light of these bounds, the original motivations for SUSY are still as persuasive as they were in the pre-LHC era.
09.01.14 (Thursday)
16:15, ESO Auditorium, Munich Joint Astronomy Colloquium
"Dynamics and Origin of the Milky Way Bulge"
Ortwin Gerhard (MPE)
Download (FLV) | Watch video / abstract
14.01.14 (Tuesday)
12:30, ESO room D29, Lunch Talk
"Dense gas tracers and star formation laws: Multiple transitions of CS in nearby active star-forming galaxies"
Zhi-Yu Zhang (UK ATC, Royal Observatory, Edinburgh)
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"Dense gas tracers and star formation laws: Multiple transitions of CS in nearby active star-forming galaxies"

Zhi-Yu Zhang (UK ATC, Royal Observatory, Edinburgh)

Abstract
In this talk, I will present our surveys of multiple CS transitions (from J=1→0 to 7→6) in nearby active star-forming galaxies, with the JVLA, GBT 100m, IRAM 30m, SMT 10m, and APEX 12m. The sample includes normal spiral galaxies, starburst, and ULIRGs. We find linear correlations between the luminosities of dense gas (L_dense) and IR emission (L_IR) for all CS transitions. These correlations even extend over eight orders of luminosity magnitude down to Galactic dense cores, and are likely tenable for all densities > 10^4 cm−3 , which indicates that star formation is not related to free-fall time scale for the dense molecular gas. For the first time we prove that irrespective of the critical density of a specific transition, dense molecular gas is universally related to star forming activities for self-gravitational bound gas systems.
16.01.14 (Thursday)
16:15, ESO Auditorium, Munich Joint Astronomy Colloquium
"Probing the physical properties of Kuiper Belt Objects"
Emannuel Lellouch (Observatoire de Paris, France)
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"Probing the physical properties of Kuiper Belt Objects"

Emannuel Lellouch (Observatoire de Paris, France)

Abstract
Once thought to be restricted to Pluto, the outskirts of the Solar System beyond Neptune are now known to harbor a collection of small bodies, the Kuiper Belt objects which represent the remnants of planetesimals that formed during the early phases of planetary accretion. With over 1300 known objects, the orbital characterization of this Trans-Neptunian population (TNOs) is now relatively well established, showing several population families (classical, resonant, scattered/detached, Centaurs) of various dynamical origins. The physical characterization of TNOs has also progressed significantly in the last 20 years, with numerous results obtained on their colors (from visible and IR photometry), surface composition (spectroscopy), rotation state and shape (optical light-curves) and binarity (direct imaging). In recent years, new techniques, including thermal radiometry, stellar occultations and high-resolution spectroscopy, have provided access to other fundamental parameters, such as size, mass density, albedo, and thermo-physical properties (i.e. thermal inertia and emissivity), as well as constraints on their atmospheres. Knowing these quantities is necessary not only for a complete characterization ("portrait") of the individual objects, but also, if they can be measured on a sufficiently large sample, to assess possible correlations between physical and orbital characteristics, possibly testifying of physical processes at work within the population (e.g. collisions, surface irradiation, maintenance of volatile ices...). We will discuss recent findings in the field, presenting general results on the population as a whole, as well as on several prominent objects, particularly the dwarf planets (Pluto, Eris, Haumea, and Makemake).
17.01.14 (Friday)
09:00 - 18:00, ESO Auditorium
II Star and Planet Formation Workshop
22.01.14 (Wednesday)
16:30, Cluster building, Boltzmannstr. 2, Cluster Universe Colloquium
"Stellar feedback in giant molecular clouds: supernovae or stellar winds?"
Katharina Fierlinger (TUM)
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"Stellar feedback in giant molecular clouds: supernovae or stellar winds?"

Katharina Fierlinger (TUM)

Abstract
Giant molecular clouds (GMCs) are reshuffled by feedback of massive stars: Stellar winds and supernova (SN) explosions of massive stars create bubbles in the interstellar medium (ISM) and insert newly produced heavy elements and kinetic energy into their surroundings. However, most of this energy is thermalized and immediately lost via radiative cooling. In the work presented in this talk we estimate the amount of feedback energy that is retained as kinetic energy when the bubble walls have decelerated to the sound speed of the ambient medium. We argue that the feedback of the most massive still existing star outweighs the feedback from less massive stars. Thus, our numerical simulations follow the evolution of a 60 solar mass star, which is the best match between the available stellar models, the assumed cloud mass and the initial mass function (IMF). Another key aspect is the relevance of stellar winds for the retained kinetic energy. In our model the wind inserts 2.34 times the energy of a SN. Additionally bubbles serve as pressure reservoirs and thus enhance the amount of energy retained as kinetic energy of the cold GMC gas. During the pressure driven phases of the bubble evolution the retained energy depends on the scales of the mixing processes in the ISM. Without the wind of the progenitor only 0.1 percent of the SN energy input are retained, whereas taking into account wind-blown bubbles, feedback energy efficiencies of a few percent can be reached.
23.01.14 (Thursday)
16:15, ESO Auditorium, Munich Joint Astronomy Colloquium
"Simulating galaxy formation: numerical and physical uncertainties"
Debora Sijacki (IoA, Cambridge)
Download (FLV) | Watch video / abstract
28.01.14 (Tuesday)
12:30, ESO old Council Room, Lunch Talk
"Extreme (and not so extreme!) gas properties in the center of our Galaxy"
Betsy Mills (NRAO)
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"Extreme (and not so extreme!) gas properties in the center of our Galaxy"

Betsy Mills (NRAO)

Abstract
Gas in the central parsecs of our Galaxy is subject to a harsh environment, including the close proximity of a supermassive black hole, supernova remnants, and massive star clusters. By characterizing the molecular gas conditions in this region, we can quantify the effect that the resulting shocks, x-rays, and cosmic rays have on gas properties and eventually star formation in this region. I will present a combination of results from the APEX, VLA, and GBT telescopes which place new limits on the large densities, temperatures, and turbulent line widths found in the molecular gas in the central 100 parsecs. Close to the black hole, we use data from the APEX telescope, to study the gas density in the Circumnuclear disk (CND), finding that it is not stable against tidal disruption. Almost all clumps appear to be transient and unlikely to form stars. We additionally find that reprocessed dust radiation from the central star cluster appears to be contributing to radiative excitation of HCN in the CND, which may lower the gas densities inferred using this molecule. Farther from the black hole, I will present larger scale VLA and GBT surveys of gas temperatures and turbulence in Galactic center clouds, including new detections of a 400 K gas component which may be shock heated, and finally new hints of cooler and less turbulent clumps embedded within these clouds.
29.01.14 (Wednesday)
16:30, Cluster building, Boltzmannstr. 2, Cluster Universe Colloquium
"Flavour and Symmetries"
Claudia Hagedorn (TUM)
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"Flavour and Symmetries"

Claudia Hagedorn (TUM)

Abstract
The Standard Model of particle physics has been very successful in describing gauge interactions, however it cannot answer the fundamental questions of the flavour sector: why are there three generations of elementary particles; why do they have the same gauge quantum numbers, but vastly different masses; why is the mass hierarchy among charged fermions much stronger than among neutrinos and why are the quark mixing angles small, while two of the mixing angles in the lepton sector are large and might be described with special mixing patterns. In many extensions of the Standard Model these fundamental questions are also not addressed. Even more, in such extensions additional particles and interactions are present which lead to large flavor violating signals, if the flavor structure is not highly constrained. Flavour symmetries which act on the space of the three generations of particles, very much like the color gauge group SU(3) on the color indices of the quarks, can play the key role in understanding the features of fermion masses and mixing and can help to efficiently suppress flavour violating signals in theories beyond the Standard Model. The focus of this talk is on symmetries and approaches which can explain the observed lepton mixing angles and make predictions for the yet unknown leptonic CP phases.
30.01.14 (Thursday)
12:30, Cluster building, Boltzmannstr. 2, Fruits of the Universe series
"The mystery of the origin of planets"
Barbara Ercolano (LMU)
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"The mystery of the origin of planets"

Barbara Ercolano (LMU)

Abstract
According to the current paradigm, planet formation comes for free together with star formation. However, the detailed physics governing this formation process is quite complex and demands huge efforts on both sides, in theoretical physics as well as in astronomical observations.

Since about two decades, we know that our solar system is not unique, and meanwhile many exoplanets have been found – also thanks to space-based missions like Kepler. Theorists have to use supercomputers to simulate the physical processes, e.g. in the framework of radiative hydrodynamics. Astrophysicist Barbara Ercolano will introduce this modern and fascinating field of astronomy and tell us if there is another earth out there.
16:15, ESO Auditorium, Munich Joint Astronomy Colloquium
"Cosmological implications of the clustering of galaxies in BOSS"
Ariel Sanchez (MPE)
Download (FLV) | Watch video / abstract

February 2014

04.02.14 (Tuesday)
10:00, ESO room Tucana (new building), Star and Planet Formation Seminar
"The Jet-Accretion Connection in Young Stellar Objects"
Roberto Galvan-Madrid (ESO)
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"The Jet-Accretion Connection in Young Stellar Objects"

Roberto Galvan-Madrid (ESO)

Abstract
I will give an update on a program that we are carrying to test the link between accretion and ejection in young stellar objects (YSOs). The idea is to do time monitoring using tracers of both accretion and ejection of full, nearby star formation regions, therefore including YSOs at each evolutionary stage. The first component of the project is a radio monitoring with the JVLA started in mid 2012. I will show our first results quantifying the radio variability in Corona Australis, which arises from a combination of free-free from radio jets and synchrotron from magnetospheres, depending on the evolutionary stage. I will also show preliminary results of a 0.5x0.5 deg radio mosaic in Ophiucus. The second component of the project is a near-infrared monitoring in the same fields. Although this part initially suffered from several problems, now we are successfully monitoring Corona Australis with the KMOS multi-IFU on the VLT, using lines such as Br Gamma and H_2 in the K band. I will show some preliminary results from the KMOS SV season and ask for advice/help on ancillary NIR observations that we could use.
12:30, ESO Auditorium (old building), Lunch Talk
"Treasure trove OmegaCAM"
Gijs Verdoes Kleijn (Leiden University)
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"Treasure trove OmegaCAM"

Gijs Verdoes Kleijn (Leiden University)

Abstract
The OmegaCAM wide-field imager at the VST at ESO Paranal is over 2 years in science operations. Three public surveys are being observed in parallel: KiDS, ATLAS and VPHAS+. Together with the VISTA surveys they provide a view on the Southern Hemisphere from u to K at unprecedented depth and spatial resolution. In addition, the Dutch astronomical community has access to almost 1 year of guaranteed time in the coming ten years.
In this talk I focus on the science being pursued with OmegaCAM in the Netherlands. It includes the Galaxy (ultracompact binaries, stellar streams), galaxy evolution (Local Group, Fornax, Hercules Supercluster) and cosmology (dark matter, dark energy, quasars at extreme redshifts).
05.02.14 (Wednesday)
16:30, Cluster building, Boltzmannstr. 2, Cluster Universe Colloquium
"TNOs are Cool - A Herschel survey of the trans-Neptunian region"
Esa Vilenius (MPE)
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"TNOs are Cool - A Herschel survey of the trans-Neptunian region"

Esa Vilenius (MPE)

Abstract
Trans-Neptunian objects (TNOs) are primitive remnants of the planetesimal disk from which the planets of our solar system formed. They are analogues to the parent bodies of dust in debris disks observed around other stars. Since 1992 about 1500 TNOs have been discovered but their basic physical properties have been challenging to measure. The richness of dynamical structure and varying physical properties set constraints to models of solar system formation and evolution. Herschel Space Observatory open time key program "TNOs are Cool" observed a sample of 130 TNOs at far-IR wavelengths around their thermal peaks. The results of radiometric modeling give albedo and size distributions as well as thermal properties. For binary systems we obtain an insight in their densities as a function of size. Thermal light curves of selected targets observed by Herschel are used together with the optical ones to solve the ambiguity between shape effects and albedo variegation. Possible correlations between physical properties, orbital elements and colors are also discussed.
06.02.14 (Thursday)
16:15, ESO Auditorium (old building), Munich Joint Astronomy Colloquium
"Probing the end of the reionization epoch with the most distant galaxies"
Laura Pentericci (INAF - Astronomical Observatory of Rome)
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"Probing the end of the reionization epoch with the most distant galaxies"

Laura Pentericci (INAF - Astronomical Observatory of Rome)

Abstract
The epoch of re-ionization is a fascinating time in the history of the Universe and many uncertainties still plague our understanding of when and how it occurred.

Lyman alpha emitting galaxies at high redshift offer a powerful probe to study both reionization and the process of galaxy formation. In particular Lyman alpha emission is an efficient tool for identifying young galaxies and for measuring how much neutral hydrogen is present in the environment of the galaxies, thus providing a reionization test that is independent of the Gunn-Peterson trough observations in quasar spectra.

The last few years have seen a number of discoveries that offered the first glimpse of the Universe at z =7, using both space and ground-based telescopes. I will review the most recent observational results on high redshift galaxies, namely Ly alpha emitters and Lyman break galaxies. In particular I will review the current constrains that we can place on the reionization epoch using the first statistical samples of spectroscopically confirmed z=7 Lyman break galaxies, the evolution of the luminosity functions and of the clustering strength of Ly alpha emitters.
I will finally present very recent ALMA observations which reveal, for the first time the nature and physical properties of these primeval galaxies that were probably responsible for the reionization.
11.02.14 (Tuesday)
12:30, ESO Auditorium (old building), Lunch Talk
"Probing the formation conditions of massive clusters with formaldehyde"
Adam Ginsburg (ESO)
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"Probing the formation conditions of massive clusters with formaldehyde"

Adam Ginsburg (ESO)

Abstract
Massive clusters are important tracers of star formation in galaxies and laboratories for the study of massive star formation and populations. Because they are rare and therefore distant, neither the population of these clusters nor the details of their assembly are well understood.

I will discuss the importance of these clusters and some theoretical formation mechanisms. I will focus on two well-known regions, the massive forming cluster W51 (not M51) and the potentially pre-star-forming cloud G0.253+0.016, aka The Brick or The Lima Bean. We have used formaldehyde as a probe of physical conditions in these regions, mapping the gas density and examining properties of the turbulence. In The Brick, we find that the mean density is very low, which explains the low observed star formation activity but raises questions about the geometry and dust properties. In W51, the density structure is highly varied, from an n~100 cm^-3 infrared dark cloud to the n~10^5 cm^-3 massive clump. Overall, the gas seems to favor a more prolonged formation scenario for massive clusters.
13.02.14 (Thursday)
16:15, ESO Auditorium (old building), Munich Joint Astronomy Colloquium
"Fermi observations of blazars and constraints on the location of the gamma-ray emission region"
Juri Poutanen (University of Turku, Finland)
Download (FLV) | Watch video / abstract
18.02.14 (Tuesday)
12:30, ESO room Fornax (old Council Room), Lunch Talk
"HI lines in Young Stellar Objects: a probe of accretion and circumstellar properties"
Simone Antoniucci (INAF - Astronomical Observatory of Rome)
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"HI lines in Young Stellar Objects: a probe of accretion and circumstellar properties"

Simone Antoniucci (INAF - Astronomical Observatory of Rome)

Abstract
HI recombination lines at optical/near-IR wavelengths are a powerful diagnostic tool for the study of Young Stellar Objects (YSOs). On the one hand these lines are commonly used as a tracer of the mass accretion process, on the other hand they can also be employed to probe the physical properties of the gas in the circumstellar structures of young sources. In this talk I will present two different applications of the analysis of HI lines.

In the first part I will talk about the POISSON project (Protostellar Optical-Infrared Spectral Survey On NTT), a large low-resolution spectral survey of 150 YSOs from five different star-forming regions. In this work we used the near-IR HI lines as a proxy for the mass accretion rate (using empirical relationships connecting line flux to the accretion luminosity), thus obtaining a large database of values, which allowed us to study in particular the time evolution of the accretion rate.

In the second part I will present the preliminary results of the analysis of the HI decrements (i.e. the flux ratio of the lines of a series relative to one used as reference) observed on X-Shooter spectra of a sample of YSOs in Lupus. X-Shooter, with its broad wavelength coverage and moderate spectral resolution, is the perfect instrument to study the HI decrements of the Balmer, Paschen, and Brackett series. I will discuss the potential and limitations of the decrement analysis to provide information on the properties of the emitting gas and of the central source. In particular, I will focus on the correlations between the decrement shape, the observed line profiles, and the (stellar and accretion) properties of the objects.
20.02.14 (Thursday)
16:15, ESO Auditorium Telescopium (old building), Munich Joint Astronomy Colloquium
"Type Ia supernova progenitors: what do we know and what not?"
Gijs Nelemans (Radboud Univ. Nijmegen)
Download (FLV) | Watch video / abstract
25.02.14 (Tuesday)
12:30, ESO room Fornax (old Council Room), Lunch Talk
"3D hydrodynamical simulations of cool stars for the interpretation of the stellar surfaces images, the fundamental parameters, the stellar variability and the planet detection"
Andrea Chiavassa (Observatoire de la Cote d'Azur, Nice)
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"3D hydrodynamical simulations of cool stars for the interpretation of the stellar surfaces images, the fundamental parameters, the stellar variability and the planet detection"

Andrea Chiavassa (Observatoire de la Cote d'Azur, Nice)

Abstract
Nowadays, the development of the observational instruments is so high that became very sensitive to the details of stellar surface. The interpretation of the stellar surfaces images, the fundamental parameters, the stellar variability and the planet detection needs realist simulations of stellar convection. Three-­dimensional radiative hydrodynamics simulations of cool stars are essential to a proper and quantitative analysis of these observations. I will present how these simulations across the Hertzsprung-Russel diagram have been (and will be) crucial to prepare and interpret the spectrophotometric, interferometric, astrometric, and imaging observations.
27.02.14 (Thursday)
12:30, Cluster building, Boltzmannstr. 2, Fruits of the Universe series
"Strange hadrons in a strongly-interacting environment: from nuclei ad astra"
Kirill Lapidus (TUM)
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"Strange hadrons in a strongly-interacting environment: from nuclei ad astra"

Kirill Lapidus (TUM)

Abstract
Measurements of hadron properties inside the nuclear environment give insight into the fundamental properties of the strong interaction in the low energy domain — confinement and broken chiral symmetry. An additional motivation to focus on the strange hadron species (kaons and hyperons) is given by the hypothesis of their appearance in the core of a neutron star. In this talk, Kirill Lapidus will outline the mechanisms and experimental constraints for the existence of strangeness in neutron stars and give an example of accelerator-based studies with a recent high-precision measurement of neutral kaons done at the HADES experiment (GSI, Darmstadt).
16:15, ESO Auditorium Telescopium (old building), Munich Joint Astronomy Colloquium
"What did we learn about the Milky Way during the last decade, and what shall we learn using Gaia and LSST?"
Zeljko Ivezic (University of Washington)
Download (FLV) | Watch video / abstract

March 2014

04.03.14 (Tuesday)
10:00, ESO room "Tucana", Star and Planet Formation Seminar
"Filaments in Serpens"
Veronica Roccatagliata (USM)
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"Filaments in Serpens"

Veronica Roccatagliata (USM)

Abstract
Filamentary molecular structures are thought to be the consequence of thermal and dynamical instabilities caused by collisions of large-scale warm flows or by the collision of two Giant Molecular Clouds. A unique laboratory to discriminate the origin of the filaments is represented by the Serpens molecular cloud. By reducing and analyzing the Herschel far-infrared observations of the Serpens core region we revealed for the first time a network of filaments converging into the core cluster. This region is the ideal region to study all the processes of star formation, from the first stages of still in-falling gas to pre-/proto-stellar gaseous and dusty condensations, as well as already formed young stars. In this talk I will present the Herschel PACS and SPIRE mosaics of this region. The temperature and column density maps of the region enable us to characterize the cloud structure, as well as the filaments network converging into the central core cluster. I will present also the results of the comparison of our analysis with simulations of turbulent molecular clouds where very similar structures form on timescales of roughly on one cloud free-fall time.
12:30, ESO room "Fornax", Lunch Talk
"Understanding AGN clustering: the need for two accretion modes"
Nikolaos Fanidakis (MPIA Heidelberg)
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"Understanding AGN clustering: the need for two accretion modes"

Nikolaos Fanidakis (MPIA Heidelberg)

Abstract
AGN inhabit a wide range of dark-matter halo environments; from the centres of clusters, where radio galaxies reside, to average Milky-Way like haloes in which quasars are found. In my talk, I will demonstrate that the variety of AGN environments can be explained when more than one accretion modes are responsible for fuelling the growth of black holes. I will show this by means of semi-analytic modelling, combined with detailed SPH simulations of galaxies in a Λ cold dark matter universe with AGN feedback. With these tools, I will explain how the large scale environment of AGN depends on luminosity and AGN type, and I will demonstrate how AGN can be used, along with line-emitting galaxies, to pinpoint the location of galaxy protoclusters in the high-redshift Universe.
06.03.14 (Thursday)
16:15, ESO Auditorium "Telescopium", Munich Joint Astronomy Colloquium
"The Astrophysics of Stellar Clusters"
Melvyn Davies (Lund Observatory)
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"The Astrophysics of Stellar Clusters"

Melvyn Davies (Lund Observatory)

Abstract
Stellar clusters are common. Globular clusters contain some of the oldest stars, whilst the youngest stars are found in OB associations or in other clusters associated with recent star formation. Such crowded places are hostile environments: a large fraction of stars will collide or undergo close encounters. I will explain how stellar clusters are factories for producing exotic objects, including potentially intermediate-mass black holes which can grow into supermassive black holes in galactic nuclei. I will also discuss how planetary systems similar to our own solar system are vulnerable within stellar clusters due to interactions with other stars. Thus by studying stellar clusters we will learn more about the rarity of planetary systems similar to our own solar system. I will explain how the depletion of red giants in the very centre of our own galaxy may tell us something about its history.
11.03.14 (Tuesday)
12:30, ESO room "Fornax", Lunch Talk
"An advanced scattered moonlight model for Cerro Paranal"
Amy Jones (University of Innsbruck)
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"An advanced scattered moonlight model for Cerro Paranal"

Amy Jones (University of Innsbruck)

Abstract
In the current era of precision astronomy, a complete sky background model is crucial, especially as the telescopes become even larger in the next decade. Such a model is needed for planning observations as well as understanding and correcting the data for the sky background. We have developed a sky model for this purpose, and it is the most complete and universal sky model that we know of to date (Noll et al. 2012). It covers a wide range of wavelengths from 0.3 to 30 microns up to a resolution of 1,000,000 and is instrument independent.

The brightest natural source of optical light at night is the Moon, and it is the major contributor to the astronomical sky background. We have an improved scattered moonlight model (Jones et al. 2013), where all of the components are computed with physical processes or observational data with less empirical parametrizations. This model is spectroscopic from 0.3 to 2.5 microns and was studied with a FORS1 (Patat et al. 2008) and dedicated X-Shooter data set. To our knowledge, this is the first spectroscopic model extending into the infrared.

I will introduce the sky background model and scattered moonlight model. Then I will go into more detail about the scattered moonlight model and present its current status as well as its performance in the optical and near-infrared.
12.03.14 (Wednesday)
16:30, Cluster building, Boltzmannstr. 2, Cluster Universe Colloquium
"Massive neutrinos and the tension between Large Scale Structure and the Cosmic Microwave Background"
Richard Battye (University of Manchester)
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"Massive neutrinos and the tension between Large Scale Structure and the Cosmic Microwave Background"

Richard Battye (University of Manchester)

Abstract
There appear to be tensions between published measurements of the amplitude of density fluctuations on large scale made by the CMB temperature anisotropies and on smaller scales by large-scale structure probes. These include cluster counts, weak gravitational lensing (both of the CMB and galaxies) and redshift space distortions. We discuss this tension and the possible explanations. These include incorrect interpretation of the observations and the possible addition of new physics to the standard model of cosmology. In particular we calculate the neutrino masses (both for active and sterile species) that would be need to resolve the discrepancy. Prime facie there is a preference of around 4 standard deviations for non-zero neutrino masses.
13.03.14 (Thursday)
12:30, Cluster building, Boltzmannstr. 2, Fruits of the Universe series
"SUSY, where are you? The concept of supersymmetry and the status of experimental searches"
David Straub (TUM)
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"SUSY, where are you? The concept of supersymmetry and the status of experimental searches"

David Straub (TUM)

Abstract
Supersymmetry can be seen as the only way to non-trivially extend the symmetries of space-time (without increasing the number of dimensions). But besides being interesting conceptually, supersymmetry also has interesting phenomenological consequences. Supersymmetrizing the Standard Model, one finds that gauge couplings extrapolated to very short distances unify and a candidate for the dark matter of the universe emerges. Most importantly, supersymmetry is the only known way to reconcile an elementary Higgs boson - that we seem to have just discovered - with the presence of new physics at high energy scales, that is required for many reasons, without excessive fine-tuning in fundamental parameters. So far however, no signs of supersymmetric partners of the known particles have shown up at the 8 TeV LHC, and rumours about the demise of supersymmetry are spreading. David will give a critical review of the motivations for and the state of low-energy supersymmetry after 3 years of LHC.
16:15, MPA large seminar room E.0.11, Munich Joint Astronomy Colloquium
"AGN feedback though the cosmic times"
Fabrizio Fiore (INAF - Astronomical Observatory of Rome)
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"AGN feedback though the cosmic times"

Fabrizio Fiore (INAF - Astronomical Observatory of Rome)

Abstract
Why do black holes in galactic nuclei have masses proportional to bulge masses and luminosities? Why did galaxies at a certain point of their cosmological evolution, stop to form stars? What is the path(s) and the mechanism(s) leading the transition from gas rich, star-forming galaxies, to red passive galaxies, deprived of all their gas? Theory and few observations suggest that AGN driven super winds (=feedback) play a major role in all these transformations. The two main building blocks of this scenario are: 1) AGN outflows, which inject energy in their environment; 2) the interaction of these flows with the galaxy interstellar matter, and its physical/chemical/geometrical modification.

I will first review AGN outflows seen in different gas phases and at different scales. I will then present searches for "direct" evidence of AGN feedback in bright nearby AGN, linking accretion and ejection occurring on sub-parsec scale in galaxy nuclei to the transformations occurring in the rest of the galaxy. I will finally discuss the perspectives of extending these studies up to z=1-3, the golden epoch of AGN and galaxy activity.
18.03.14 (Tuesday)
10:00, ESO room "Fornax", Star and Planet Formation Seminar
"The formation of filamentary bundles in turbulent molecular clouds"
Nick Moeckel (USM)
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"The formation of filamentary bundles in turbulent molecular clouds"

Nick Moeckel (USM)

Abstract
The classical picture of a star-forming filament is a near-equilibrium structure, with collapse dependent on its gravitational criticality. Recent observations have complicated this picture, revealing filaments as a mess of apparently interacting subfilaments, with transsonic internal velocity dispersions and mildly supersonic intra-subfilament dispersions. How structures like this form is unresolved. I will discuss a study of the velocity structure of filamentary regions in a simulation of a turbulent molecular cloud. I'll talk about two main findings: first, the observed complex velocity features in filaments arise naturally in self gravitating hydrodynamic simulations of turbulent clouds without the need for magnetic or other effects. Second, a region that is filamentary only in projection and is in fact made of spatially distinct features can displays these same velocity characteristics. The fact that these disjoint structures can masquerade as coherent filaments in both projection and velocity diagnostics highlights the need to continue developing sophisticated filamentary analysis techniques for star formation observations.
12:00, ESO room "Fornax", Lunch Talk
***note the earlier-than-usual time***
"Ground based optical tracking of the Gaia satellite"
Martin Altmann (Centre for Astronomy of the University of Heidelberg)
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"Ground based optical tracking of the Gaia satellite"

Martin Altmann (Centre for Astronomy of the University of Heidelberg)

Abstract
The recently launched Gaia satellite mission will provide astronomers with an astrometric dataset comprising data on 1 billion stars of unprecedented precision. In order to fully exploit the capabilities of Gaia, the location and velocity vector of the space craft itself need to be known to a high degrees, more precisely than conventional means can deliver. For this reason a network of small to medium telescopes was set up to track the satellite astrometrically. The overall structure and strategy of this campaign will be described in this presentation. Since the launch of Gaia, the GBOT group had to enter a process of redefinition and reassessment of its strategy after the target turned out to be ~3 mags fainter than anticipated. The actions taken and the current status of the effort will be reviewed and commented on.
19.03.14 (Wednesday)
16:30, Cluster building, Boltzmannstr. 2, Cluster Universe Colloquium
"The Majorana nature of massive neutrinos as a possible hint for new physics"
Aurora Meroni (U Roma, INFN Frascati)
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"The Majorana nature of massive neutrinos as a possible hint for new physics"

Aurora Meroni (U Roma, INFN Frascati)

Abstract
Determining the nature - Dirac or Majorana - of massive neutrinos, possibly related to a New Physics scale beyond that predicted by the Standard Model is a fundamental problem under study. Significant experimental efforts have been made to unveil the possible Majorana nature of massive neutrinos by searching for neutrinoless double beta decay with increasing sensitivity. These constraints, together with the results from beta-decay experiments and in light of the recent (and future) cosmological observations can be combined in order to extract information on new possible couplings in the Lagrangian of particle interactions, changing the total lepton charge L=L_e + L_\mu + L_\tau by two units. Further if it will be experimentally established the Majorana nature of massive neutrinos, via the observation of the double beta decay, it will be possible to test the compatibility of the usual 3-neutrino scenario with the possible existence of 1 or 2 additional sterile neutrino states with masses at the eV scale (the so called 3+1 and 3+2 schemes) and to study the implications of all this on the general properties of the neutrino mass matrix.
20.03.14 (Thursday)
16:15, ESO Auditorium "Telescopium", Munich Joint Astronomy Colloquium
"Massive black holes: dynamics, spin evolution and gravitational wave detection"
Alberto Sesana (AEI Potsdam)
Abstract
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"Massive black holes: dynamics, spin evolution and gravitational wave detection"

Alberto Sesana (AEI Potsdam)

Abstract
Within this decade the detection of gravitational waves (GWs) may be a reality, opening a completely new window on the Universe. The low frequency window will be dominated by signals emitted by a cosmological population of massive black hole binaries (MBHBs). In this talk I will review several aspect of MBH physics focusing in particular on spin evolution and gravitational wave emission. In the first part of the talk, I will present a model linking the accretion flow to the kinematical properties of the galaxy hosts, which produces MBH spins in broad agreement with current observations. In the second part, I will pay particular attention to the prospect of GW detection from MBHBs with pulsar timing arrays and/or future space based interferometers.
25.03.14 (Tuesday)
10:00, ESO room "Tucana", Star and Planet Formation Seminar
"Detectable Glycine in Solar-type System Precursors: Implications for ALMA Band2"
Izaskun Jimenez-Serra (ESO)
Abstract
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"Detectable Glycine in Solar-type System Precursors: Implications for ALMA Band2"

Izaskun Jimenez-Serra (ESO)

Abstract
Glycine (NH2CH2COOH) is the simplest amino acid. Its detection is key to understand the formation mechanisms of pre-biotic molecules in the interstellar medium and their subsequent delivery onto planetary systems. Glycine has extensively been searched for toward hot molecular cores, although these studies did not yield any firm detection. In contrast to hot cores, low-mass star forming regions, and in particular their earliest stages represented by cold pre-stellar cores, may be better suited for the detection of glycine. In this work, we have carried out 1D spherically symmetric radiative transfer calculations of the glycine emission expected to arise from a low-mass pre-stellar core, L1544. Water vapour has recently been reported toward this core, indicating that a small fraction of the grain mantles in L1544 (~0.5%) has been injected into the gas phase. Assuming that glycine is photo-desorbed together with water in L1544, and considering a solid glycine abundance of 1E−8, our calculations reveal that several glycine lines between 67GHz and 85GHz have detectable peak intensities larger than 10mK. The development of the receivers for ALMA Band 2+3 will open up the possibility to detect glycine and other pre-biotic molecules at the earliest stages of the formation of proto-Solar systems, possibly allowing the connection between the pre-biotic chemistry in the ISM and its subsequent delivery onto protoplanetary systems.
12:30, ESO room "Fornax", Lunch Talk
"Multi-wavelength models of galaxy formation: evidence for a varying IMF?"
Cedric Lacey (Durham University, UK)
Abstract
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"Multi-wavelength models of galaxy formation: evidence for a varying IMF?"

Cedric Lacey (Durham University, UK)

Abstract
I will present latest results from our work on multi-wavelength modelling of the evolution of galaxies. The work combines a theoretical model of galaxy formation based on Lambda-CDM with a radiative transfer calculation of the reprocessing of stellar emission by dust in galaxies. Our previous work implied the need for a top-heavy IMF in starbursts in order to explain the number counts and redshifts of sub-mm galaxies in this framework, once the observational constraints from the present-day galaxy luminosity function at optical and near-IR wavelengths were included. We have revisited this using an improved galaxy formation model, which includes a more realistic treatment of star formation, as well as feedback from AGN. In the new work, we also impose the constraint that the model reproduces the observed evolution of the galaxy luminosity function at near-IR wavelengths. We find that variations in the IMF still seem to be required when we try to match all of these observational constraints simultaneously.
27.03.14 (Thursday)
12:30, Cluster building, Boltzmannstr. 2, Fruits of the Universe series
"Embedding Peanuts in Galaxies"
Panos Patsis (Academy of Athens)
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"Embedding Peanuts in Galaxies"

Panos Patsis (Academy of Athens)

Abstract
Many disk galaxies observed edge-on have a boxy or peanut-shaped central structure. The Milky Way is one of them. We speak about "b/p-bulges" that in some cases have even the morphology of X-shaped cores. They are considered being parts of bars. The talk will be about the dynamical mechanisms that can create these structures in galactic disks. Their orbital content will be discussed and it will be explained how the theory of chaos helps in understanding the robustness of boxes and peanuts.
16:15, ESO "new" Auditorium "Eridanus", Munich Joint Astronomy Colloquium
"Probing the Primordial Universe with Galaxy Clustering and Shapes"
Fabian Schmidt (MPA)
Download (FLV) | Watch video / abstract
28.03.14 (Friday)
12:30, ESO room "Fornax", Lunch Talk
"What is the most powerful and persistent engine of Nature?"
Gabriele Ghisellini (INAF - Astronomical Observatory of Brera, Italy)
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"What is the most powerful and persistent engine of Nature?"

Gabriele Ghisellini (INAF - Astronomical Observatory of Brera, Italy)

Abstract
We realized long ago that accretion onto compact objects was a more efficient engine than thermonuclear reactions. Relativistic jets, however, seem to carry more power than what accretion can provide. I will present the evidences for this statement by considering the jets of blazars, and finding robust results about their power.

April 2014

01.04.14 (Tuesday)
12:30, ESO room "Fornax", Lunch Talk
"The nature of dusty star-forming galaxies (a post-Herschel view)"
Lingyu Wang (Durham University)
Abstract
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"The nature of dusty star-forming galaxies (a post-Herschel view)"

Lingyu Wang (Durham University)

Abstract
Combining Herschel with data at other wavelengths enables us to study different physical processes that are at work. In my talk I will present results from two recent projects that I have (co-)led. The first project probes the co-evolution of black hole growth and star formation by studying the cross-correlation between optically selected type 1 SDSS quasars and the CIB. For the first time, we detect not only the sub-millimetre emission of the quasars themselves which dominates on small scales but also the correlated emission of dusty star-forming galaxies on larger scale. The correlated emission comes from satellite galaxies in the same halo as the quasar and galaxies which reside in separate halos correlated with the quasar-hosting halo. The second project looks at the cross-correlation between the CIB and the cosmic microwave background (CMB). Apart from the dusty star-forming galaxies which are present in both the CIB and CMB maps, we also detect the cross-correlation between the thermal Sunya'ev-Zeldovich (tSZ) signal and the CIB sourced by dusty star-forming galaxies. The tSZ-CIB cross-correlation signal not only provides constraints on the level of star-formation activity in massive systems, but also significantly improves constraints on the kinetic SZ which is of great interest for studying the duration of reionization.
03.04.14 (Thursday)
16:15, ESO auditorium "Telescopium", Munich Joint Astronomy Colloquium
"Characterizing Massive Black Holes through Stellar Tidal Disruption"
Enrico Ramirez Ruiz (University of California)
Abstract
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"Characterizing Massive Black Holes through Stellar Tidal Disruption"

Enrico Ramirez Ruiz (University of California)

Abstract
A star interacting with a massive black hole cannot be treated as a point mass if it gets so close to the black hole that it becomes vulnerable to tidal distortions and even disruption. When a rapidly changing tidal force starts to compete with a star's self-gravity, the material of the star responds in a complicated way. This phenomenon poses an as yet unmet challenge to computer simulations. The art of modeling the tidal disruption of stars by massive black holes forms the main theme of my talk. Detailed simulations should tell us what happens when stars of different types get tidally disrupted, and what radiation a distant observer might detect as the observational signature of such events.
08.04.14 (Tuesday)
10:00, ESO room "Tucana", Star and Planet Formation Seminar
"Shockingly low water abundances in Herschel / PACS observations of low-mass protostars in Perseus"
Agata Karska (MPE)
Abstract
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"Shockingly low water abundances in Herschel / PACS observations of low-mass protostars in Perseus"

Agata Karska (MPE)

Abstract
Shocks produced in the outflows from young protostars strongly influence the process of star formation, yet are not well quantified. Recent far-infrared observations of molecules with Herschel offer a unique opportunity to constrain the shock parameters, such as a type of shock (continuous / jump), shock velocity and pre-shock density of envelope material. However, various authors found very different shock characteristics towards a few low-mass protostars studied so far. Here, I will present a survey of a large (~20 objects) and uniform (same distance, age, environment) sample of protostars located in Perseus Molecular Cloud observed as a part of the "William Herschel Line Legacy" program. Our analysis of different molecular line ratios shows that the currently available shock models cannot explain all the observations. The water abundances are too high, indicating that additional physical processes need to be included in the models.
12:30, ESO auditorium "Telescopium", Lunch Talk
"XXL: the ultimate XMM extragalactic survey"
Marguerite Pierre (Service d'Astrophysique, CEA Saclay)
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"XXL: the ultimate XMM extragalactic survey"

Marguerite Pierre (Service d'Astrophysique, CEA Saclay)

Abstract
At the end of 2010, a Very Large XMM programme - the XXL survey - was granted in order to map two regions of 25 deg2 each at medium sensitivity. This will lead to the detection of several hundreds of clusters of galaxies and of some 30 000 AGNs with well defined selection functions. Since 2012, an ESO Large Programme is performing the spectroscopic identification of the galaxy clusters. After reviewing the scientific motivations, we describe the some 540 XMM observations, the associated multi-wavelength follow-up and simulation programmes. We especially underline the cosmological goals of the project involving cluster number counts, large-scale studies with clusters and AGNs as well as the systematic search for very distant clusters in a multi-lambda space. This will be the occasion to review in some detail the still hotly debated question of the proper use of clusters of galaxies for cosmology, as recently revived by the tension between the cosmological constraints from the Planck CMB and the Planck clusters. We describe a new method for the cosmological analysis of cluster surveys that bypasses the traditional mass calculation step. We present the first scientific results.
09.04.14 (Wednesday)
16:30, Cluster building, Boltzmannstr. 2, Universe Colloquium
"Answers in the light: High-resolution spectra and type Ia supernovae progenitors"
Assaf Sternberg (TUM)
Abstract
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"Answers in the light: High-resolution spectra and type Ia supernovae progenitors"

Assaf Sternberg (TUM)

Abstract
A Type Ia supernovae is the very luminous thermonuclear explosion of a carbon-oxygen white-dwarf in a close binary system. Despite numerous studies, the nature of the companion star remains uncertain and under much debate. A main discriminant between the progenitor models that have been proposed is the predicted circumstellar environment in which the white-dwarf explodes. Therefore, studying the circumstellar environment of Type Ia supernovae can help us validate which progenitor channel, or channels, can lead to these brilliant events. High-resolution spectroscopy is currently the most promising method with which one can probe the circumstellar material around a Type Ia supernova, while using the supernova as back-light. This talk will present an overview of the high-spectral-resolution studies that have been performed in recent years, what we have learned from them, and what we can do in the future to get us closer to solving the long standing progenitor mystery.
10.04.14 (Thursday)
16:15, ESO auditorium "Telescopium", Munich Joint Astronomy Colloquium
"Future prospects of the cosmic noon: mapping and resolving galaxy formation at its peak epoch"
Taddy Kodama (NAOJ, Subaru Telescope)
Abstract
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"Future prospects of the cosmic noon: mapping and resolving galaxy formation at its peak epoch"

Taddy Kodama (NAOJ, Subaru Telescope)

Abstract
Our Mahalo-Subaru project has been mapping out star forming activities at 0.4<z<3.3 covering the peak epoch of galaxy formation, and across various environments. It employs a unique set of narrow-band filters on MOIRCS/Subaru to search for Ha emitters associated to the proto-clusters or in narrow redshift slices in the general field. We have shown not only filamentary/clumpy structures of all the proto-clusters but also a very rapid rise in star formation activities with the lookback time. We also show that the mode of star formation in dense environment is more burst-like and dusty compared to that in the field, due probably to galaxy-galaxy interactions. HST images from the CANDELS survey have revealed that nearly half of the Ha emitters in the field at z~2 have clumpy structures, and among them "red dusty clumps" are preferentially found near or at the mass center of galaxies. They are probably linked to bulge formation and therefore this process is expected to depend on environment.

I will also present prospects from other on-going/future major programs using a wide range of facilities from optical to (sub)mm to increase samples and investigate in more detail the physics and mode of star formation.
16.04.14 (Wednesday)
16:30, TUM Institute for Advanced Study, Lichtenbergstr. 2a, Universe Colloquium
"Quantum Universe: Theory and Observations"
Viatcheslav Mukhanov (LMU)
Abstract
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"Quantum Universe: Theory and Observations"

Viatcheslav Mukhanov (LMU)

Abstract
In March 2014 Harvard astronomers announced the detection of primordial gravitational waves with the telescope of the BICEP2 collaboration at the South Pole. They studied the polarization properties of the cosmic microwave background radiation which showed imprints of so-called B modes, relics of gravitational waves of the inflationary phase of the Universe. One of the world experts in the field of inflation theories and Principal Investigator at the Excellence Cluster Universe, Viatcheslav Mukhanov (LMU), will present the significance of these findings for theoretical cosmology.
22.04.14 (Tuesday)
12:30, ESO room "Fornax", Lunch Talk
"The EAGLE Universe"
Richard Bower (Durham University, UK)
Abstract
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"The EAGLE Universe"

Richard Bower (Durham University, UK)

Abstract
The EAGLE (Evolution and Assembly of Galaxies and their Environments) project is a suite of hydrodynamic simulations of the Universe. The simulations take into account the full range of baryonic physics, including metal dependent gas cooling, star formation, supernovae and black hole formation. The resolution of the simulations is sufficient to resolve the onset of the Jeans instability in galactic disks, allowing us to study the formation of individual galaxies in detail. At the same time the largest calculation simulates a volume that is 100 Mpc on each side, exploring the full range of galaxy environments from the isolated dwarves to rich galaxy clusters.

A key philosophy of the simulations has been to use the simplest possible sub-grid models for star formation, black hole accretion and feedback from supernovae and AGN. Efficient feedback is achieved without hydrodynamic decoupling of particles. The small number of parameters in these models are calibrated by requiring that the simulations match key observed properties of local galaxies. Having set the parameters using the local Universe, I will show that the simulations reproduce the observed evolution of galaxy properties extremely well. The resulting universe provides us with deep insight into the formation of galaxies and black holes. In particular, we can use the simulations to understand the relationship between local galaxies and their progenitors at higher redshift and to understand the role of interactions between galaxies and the AGN that they host. I will present an overview of some of the most important results from the project.
23.04.14 (Wednesday)
16:30, Cluster building, Boltzmannstr. 2, Universe Colloquium
"The safest routes to islands Beyond the Standard Model"
Francesco Riva (Ecole Polytechnique Federale de Lausanne)
Abstract
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"The safest routes to islands Beyond the Standard Model"

Francesco Riva (Ecole Polytechnique Federale de Lausanne)

Abstract
In the absence of direct discoveries, physics Beyond the Standard Model (BSM) can be parametrized by an effective field theory as an expansion in inverse powers of the New Physics scale. This expansion serves as a guide for precision searches. In fact, the leading term in this expansion coincides with the standard model: its symmetries and relations are well known and are being tested at colliders. In this talk Francesco will discuss the next order in the expansion, that parametrize the largest effects that can be expected from physics BSM. He will show that many relations persist, implying that not all the observables that we experimentally test are independent. For example, deviations in the differential distribution of h->Vff decays, are correlated with deformations of the couplings of vectors to fermions, that are already well measured at LEP at CERN.
24.04.14 (Thursday)
10:00, ESO room "Fornax", Star and Planet Formation Seminar
"Are ”Low Luminosity Objects” Young Protostars?"
Tien-Hao Hsieh (MPIfR, Bonn / National Tsing Hua University, Taiwan)
Abstract
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"Are ”Low Luminosity Objects” Young Protostars?"

Tien-Hao Hsieh (MPIfR, Bonn / National Tsing Hua University, Taiwan)

Abstract
Low Luminosity Objects (LLOs) are the faintest protostars with internal luminosity Lint < 0.2 Lo. The nature of Low Luminosity Objects is still unclear. Their low luminosities hints that they could be either very young, very low-mass, or even very young and low-mass protostars (i.e., proto-brown dwarfs). In addition, they could be at the quiescent stage of episodic accretion process. To examine whether LLOs are truly young protostars, we study the evolutionary status of 16 LLOs with radio observations. We used 12M telescope and Submillimeter Telescope (SMT) of Arizona Radio Observatory (ARO) to observe N2D+ and N2H+ line emission, and derived the N2D+/N2H+ abundance ratio which has been argued to be an evolutionary indicator in the early stage. We further use RADEX, a non-LTE molecular radiative transfer code, to derive the properties of molecular cores, such as volume density (nH2) and kinematic temperature (Tkin) which are believed to increase as a protostellar core evolves. We therefore study the relation between these age indicators and N2D+/N2H+ and our results suggest that most of our target LLOs are likely to be extremely young protostars.
16:15, ESO auditorium "Telescopium", Munich Joint Astronomy Colloquium
"Archaeology of Exo-Terrestrial Planetary Systems"
Jay Farihi (Institute of Astronomy, Cambridge)
Abstract
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"Archaeology of Exo-Terrestrial Planetary Systems"

Jay Farihi (Institute of Astronomy, Cambridge)

Abstract
We now stand firmly in the era of solid exoplanet detection via Kepler and other state of the art facilities. Yet the empirical characterization of these most intriguing planets is extremely challenging. Transit plus radial velocity information can yield planet mass and radius, and hence planet density, but the bulk composition remains degenerate and completely model-dependent. Currently, the abundances of a handful of exoplanet atmospheres can be estimated from transit spectroscopy, or observed directly via spectroscopy, but probing only the most tenuous outer layers of those planets.

Fortunately, as demonstrated by Spitzer and complementary ground-based observations, debris disk-polluted white dwarfs can yield highly accurate information on the chemical structure of rocky minor planets (i.e. exo-asteroids), the building blocks of solid exoplanets. The white dwarf distills the planetary fragments, and provides powerful insight into the mass and chemical structure of the parent body.

This archaeological method provides empirical data on the assembly and chemistry of exo-terrestrial planets that is unavailable for any planetary system orbiting a main-sequence star. In the Solar System, the asteroids (or minor planets) are leftover building blocks of the terrestrial planets, and we obtain their compositions - and hence that of the terrestrial planets - by studying meteorites. Similarly, one can infer the composition of exo-terrestrial planets by studying tidally destroyed and accreted asteroids at polluted white dwarfs.

I will present ongoing, state of the art results using this unconventional technique, including the recent detection of terrestrial-like debris in the Hyades star cluster, as well as the detection of water-rich planetesimals that may represent the building blocks of habitable exoplanets.
29.04.14 (Tuesday)
12:30, ESO room "Fornax", Lunch Talk
"The maturing stellar populations of X-ray selected AGN host galaxies"
Antonio Hernan-Caballero (Instituto de Fisica de Cantabria, Spain)
Abstract
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"The maturing stellar populations of X-ray selected AGN host galaxies"

Antonio Hernan-Caballero (Instituto de Fisica de Cantabria, Spain)

Abstract
Comparative studies of the restframe colours of active and inactive galaxies have shown no clear differences when the stellar mass-dependency of the AGN fraction is taken into account. This is in contrast to the observation of a lower frequency of AGN in quiescent galaxies, and specific star formation rates in AGN hosts that are comparable to those in star-forming galaxies at the same redshift. In this talk I will show recent results from the Survey for High-z Absorption Red and Dead Sources (SHARDS) that provide an interpretation of these two apparently contradictory observations.
30.04.14 (Wednesday)
16:30, Cluster building, Boltzmannstr. 2, Universe Colloquium
"How to travel to the stars and Fermi's paradox"
Andreas Hein (TUM)
Abstract
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"How to travel to the stars and Fermi's paradox"

Andreas Hein (TUM)

Abstract
Since the dawn of civilization humans have imagined travelling to the stars and have asked, whether we are alone in the universe. However, it is only about 50 years that interstellar travel has moved into the realms of physical and technological feasibility. It is also about 50 years that humanity has made first steps to search for extraterrestrial intelligence. From Freeman Dyson’s Project Orion to Project Daedalus to more recent studies, this talk gives an overview of the most promising ways to travel to the stars from today’s perspective, as well as its relevance for the so-called Fermi’s paradox. In particular, a spacecraft concept study based on inertial confinement fusion propulsion will be presented, conducted by a team of volunteers at TUM and an alternative approach using laser-driven sails. The question of interstellar travel has direct relevance for Fermi’s paradox, which asks the question: If there is extraterrestrial intelligence, why can’t we find any evidence for their existence? Various possible solutions to Fermi’s paradox have been proposed and some will be presented. More recent contributions link Fermi’s paradox with the Doomsday Argument and existential risks, leading to possibly gloomy prospects for our own survival in the universe.

May 2014

06.05.14 (Tuesday)
10:00, ESO room "Tucana", Star and Planet Formation Seminar
"The Mdot-M_* relation of pre-main-sequence stars: a consequence of X-ray driven disc evolution"
Barbara Ercolano (USM)
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"The Mdot-M_* relation of pre-main-sequence stars: a consequence of X-ray driven disc evolution"

Barbara Ercolano (USM)

Abstract
I will present results from our recent paper where we analyse current measurements of accretion rates on to pre-main-sequence stars as a function of stellar mass, and conclude that the steep dependence of accretion rates on stellar mass is real and not driven by selection/detection threshold, as has been previously feared. These conclusions are reached by means of statistical tests including a survival analysis which can account for upper limits. The power-law slope of the Mdot-M_* relation is found to be in the range of 1.6-1.9 for young stars with masses lower than 1 M⊙. The measured slopes and distributions can be easily reproduced by means of a simple disc model which includes viscous accretion and X-ray photoevaporation. We conclude that the Mdot-M_* relation in pre-main-sequence stars bears the signature of disc dispersal by X-ray photoevaporation, suggesting that the relation is a straightforward consequence of disc physics rather than an imprint of initial conditions.
06.05.14 (Tuesday)
12:30, ESO auditorium "Telescopium", Lunch Talk
"Absorption systems in cosmological simulations and their connection with galaxies"
Alireza Rahmati (MPA)
Abstract
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"Absorption systems in cosmological simulations and their connection with galaxies"

Alireza Rahmati (MPA)

Abstract
I will talk about the distribution of HI and metal absorbers in cosmological simulations and compare the simulation results with observations. I will further discuss the implications for the relation between absorbers and galaxies.
07.05.14 (Wednesday)
16:30, Cluster building, Boltzmannstr. 2, Universe Colloquium
"Making stars: Sodium laser guide stars in terrestrial astronomy"
Roland Holzlöhner (ESO)
Abstract
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"Making stars: Sodium laser guide stars in terrestrial astronomy"

Roland Holzlöhner (ESO)

Abstract
Terrestrial astronomy suffers from wavefront distortion due to atmospheric turbulence: The resolution limit in the visible, depending on the site, lies in the range of 0.5-2 arcseconds, corresponding to the diffraction limit of a telescope with only 6-25cm clear aperture. The detrimental effect of turbulence can be significantly mitigated with the help of adaptive optics, in which the shape of one or several mirrors in the optical train is actively controlled using a real-time closed loop system. The control signal is derived from the continuous observation of a bright star in the telescope field of view with wavefront sensors and updated at a rate of 500-1000 Hz. Since many areas of the night sky lack sufficiently bright stars, it has become common in large telescopes such as ESO's Very Large Telescope (VLT) in the Atacama desert to employ laser guide stars (LGS). To make these, a powerful laser beam is propagated onto the sky parallel to the optical axis. Sodium LGS excite a diluted natural sodium layer in the mesosphere at 80-110km altitude through resonant fluorescence at 589nm and thus provide artificial beacons to adaptive optics. In the presentation Roland will discuss the involved physics and highlight some of the technical challenges.
08.05.14 (Thursday)
12:30, Cluster building, Boltzmannstr. 2, Fruits of the Universe series
"No food, no star - the complex evolution of a galaxy star formation activity"
Paola Popesso (TUM)
Abstract
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"No food, no star - the complex evolution of a galaxy star formation activity"

Paola Popesso (TUM)

Abstract
The evolution of the star formation activity and, thus, the assembly of the stellar content of galaxies remain at the heart of galaxy evolution studies. It is now rather well established that most galaxies form stars at a "normal" level, dictated mainly by their stellar mass and regulated by secular processes. This is seen as a main sequence (MS) in the star formation rate(SFR)-stellar mass plane. The normalization of this sequence declines with time since z~2. However, we do not yet fully understand the processes that control this evolution, nor how individual galaxies evolve relative to it. While the existence of a MS may seem to suggest a simple and universal mode of star formation in galaxies (on average), the deviations indicate a more complex relation between galaxy SFRs, gas reservoir, external and internal mechanisms triggering or halting star formation. In this context Paola will discuss in particular the role of the "environment quenching" as the main external mechanism able to suppress the galaxy star formation activity.
08.05.14 (Thursday)
16:15, ESO auditorium "Telescopium", Munich Joint Astronomy Colloquium
"Accretion Disk Outbursts: MHD Simulations (Finally) Confront Reality"
Omer Blaes (UC Santa Barbara)
Download (FLV) | Watch video / abstract
13.05.14 (Tuesday)
12:30, ESO room "Fornax", Lunch Talk
"The Hot Horizontal Branch Stars in NGC 288 - Confusion, Diffusion and Why You should never Give Up!"
Sabine Moehler (ESO)
Abstract
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"The Hot Horizontal Branch Stars in NGC 288 - Confusion, Diffusion and Why You should never Give Up!"

Sabine Moehler (ESO)

Abstract
In my talk I will present the analysis of medium-resolution spectra of hot horizontal branch stars in the metal-poor globular cluster NGC 288. Equally important I will describe the pitfalls we encountered before arriving at our final results. In order not to spoil the talk no further details are given here.
15.05.14 (Thursday)
16:15, ESO auditorium "Telescopium", Munich Joint Astronomy Colloquium
"Relativistic Winds in Quasars"
George Chartas (College of Charleston)
Download (FLV) | Watch video / abstract
20.05.14 (Tuesday)
10:00, ESO room "Tucana", Star and Planet Formation Seminar
"Turbulence in Giant Molecular Clouds: The effect of photoionization feedback"
Dominika Boneberg (USM)
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"Turbulence in Giant Molecular Clouds: The effect of photoionization feedback"

Dominika Boneberg (USM)

Abstract
Giant Molecular Clouds are observed to be turbulent, but without a driving mechanism this turbulence will quickly die away. We analyze the velocity field of simulations of star forming regions and find strong indications that photoionization feedback by massive young stars can drive turbulence.
12:30, ESO auditorium "Telescopium", Lunch Talk
"The z=0.89 molecular-rich absorber toward the lensed blazar PKS1830-211"
Sebastien Muller (Onsala)
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"The z=0.89 molecular-rich absorber toward the lensed blazar PKS1830-211"

Sebastien Muller (Onsala)

Abstract
The line of sight toward the lensed blazar PKS1830-211 is remarkable for several reasons and offers the opportunity to address many astronomical interests. The 40+ molecules detected so far in the z=0.89 absorber in front of the blazar do not only tell us about the physico-chemical conditions of the molecular gas in a galaxy at a lookback time of more than half the current age of the Universe, but they can also be used as powerful cosmological probes. Based on recent radio observations, including ALMA cycle 0 data, I will present
1) a precise and accurate measurement of the cosmic microwave background temperature at z=0.89;
2) constraints of the cosmological variations of fundamental constants such as the proton-to-electron mass ratio;
3) measurements of isotopic ratios at z=0.89, and 4) I will argue that lensed blazars such as PKS1830-211 offer the unique opportunity to monitor the activity of a blazar black-hole down to unprecedented accuracy.
22.05.14 (Thursday)
12:30, ESO auditorium "Eridanus", Astronomy Talk for Non-Astronomers
"Colours from Earth"
Bob Fosbury (ESO Astronomer Emeritus)
Abstract
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"Colours from Earth"

Bob Fosbury (ESO Astronomer Emeritus)

Abstract
Choreographed by Carl Sagan in 1990, the Voyager 1 science team instructed the spacecraft to take a "Portrait of the Planets" from outside the orbits of Neptune and Pluto. Nestling in a beam of sunlight scattered within the camera, the Pale Blue Dot became an icon of human civilization. In this talk we ask what an alien observer, on a planet circling an M-dwarf star nearly eight light years from the Sun, might learn about Earth from a careful study of its blue colour. Although one of three blue planets in the Solar System, our alien would quickly realise that Earth's blue had a very different origin from the swirling, methane-tinted atmospheres of Uranus and Neptune. Although it is highly likely that the first extraterrestrial life to be discovered will be in an environment very different to Bejing or New York, the prospect of discovering 'Earth's twin' is a strong driver for exoplanet searches and characterisations.
12:30, Cluster building, Boltzmannstr. 2, Fruits of the Universe series
"Precision experiments at low energies and the early Universe"
Peter Fierlinger (TUM)
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"Precision experiments at low energies and the early Universe"

Peter Fierlinger (TUM)

Abstract
Extreme measurement precision at very low energies provides an alternative path to search for physics beyond the Standard Model of particle physics. Although very different information is obtained from such relatively small-scale experiments compared to accelerator physics, they potentially probe much higher energy scales. Next to a more general discussion of concepts and ideas in this field, several approaches based locally in Munich will be discussed.
16:15, ESO auditorium "Telescopium", Munich Joint Astronomy Colloquium
"Cepheids as standard candles: a 1% distance scale for cosmology?"
Pierre Kervella (LESIA, Observatoire de Paris)
Abstract
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"Cepheids as standard candles: a 1% distance scale for cosmology?"

Pierre Kervella (LESIA, Observatoire de Paris)

Abstract
Thanks to their period-luminosity (PL) relation, Cepheids provide one of the most accurate empirical distance scales, applicable up to at least 20 Mpc. They are in particular at the base of the calibration of secondary distance indicators, such as SN Ia.

In the era of precision cosmology, the calibration of the PL relation at the 1% level is however complicated by the fact that long-period Cepheids are too distant for direct and accurate trigonometric parallax measurements (even for GAIA). The most accurate Cepheid distances are currently based on the classical Baade-Wesselink (BW) technique, which in turn relies on surface brightness-color relations and a velocity conversion factor (the projection factor). To bypass this dependance, we applied a novel technique based on the measurement of the changes in angular diameter of Cepheids using optical long-baseline interferometry. I will present the results we obtained from interferometric observations of a sample of Galactic Cepheids, with an emphasis on the projection factor employed in BW techniques. I will also briefly discuss the influence of circumstellar envelopes on these observations, their potential impact on the distance scale, and present the special case of the dust-embedded Cepheid RS Puppis.

As they are relatively massive stars, Cepheids are often members of multiple systems. We discovered that they also host bright circumstellar envelopes, particularly at infrared wavelengths. Binarity and envelopes can both affect the apparent brightness of Cepheids, potentially biasing the calibration of the PL relation. But these properties also provide us with new tools to measure geometric distances (through binary orbits), and to better understand the evolution and complex dynamics of the Cepheid atmospheres. I will present our recent results and ongoing programs on this front.
27.05.14 (Tuesday)
12:30, ESO room "Fornax", Lunch Talk
"The astrophysics of the PLATO space mission"
Malcolm Fridlund (DLR)
Abstract
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"The astrophysics of the PLATO space mission"

Malcolm Fridlund (DLR)

Abstract
With the selection of PLATO as ESA's M3 mission, the situation for astronomical observations of exoplanets from space is going in the right direction. At the moment the global astronomical community can prepare for a number of missions - CHEOPS, TESS, JWST and PLATO - that will provide the next necessary step on the way to understand exoplanets, stars and eventually ourselves. A new science of truly comparative planetology is being born at the moment and will surely thrive fully in the 2020:ties.

PLATO, intended for a launch in the first quarter of the year 2024, will push the precision of transit photometry to the limit where it is possible to simultaneously detect the astroseismic p-modes from the host star as well as the high precision shape of the transit light curve. This will allow the determination of masses and radii of the star and planet to an accuracy of a few percent. The actual comparison between different types of planets then finally becomes possible. At the same time, it will be feasible to determine the age of exoplanetary systems to a precision of less than 10% (or typically 250 Myears), an order-of-magnitude improvement for main sequence solar type stars.

PLATO will also put strong requirements on the required ground based follow-up program, and the preparation for this will have to begin within the near future.
28.05.14 (Wednesday)
16:30, Cluster building, Boltzmannstr. 2, Universe Colloquium
"Large scale structure formation with the Schroedinger method"
Cora Uhlemann (LMU)
Abstract
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"Large scale structure formation with the Schroedinger method"

Cora Uhlemann (LMU)

Abstract
When describing large-scale structure formation of collisionless dark matter one is interested in the dynamics of a large collection of identical point particles that interact only gravitationally. Via gravitational instability initially small density perturbations evolve into eventually bound structures, like halos that are distributed along the cosmic web. Even though this problem seems quite simple from a conceptual point of view, no general solution is known and one has to resort to N-body simulations. Analytical methods to describe structure formation are in general based on the dust model which describes cold dark matter as a pressureless fluid characterized by density and velocity. This model works quite well up to the quasi-linear regime but necessarily fails when multiple streams form that are especially important for halo formation but lead to singularities in the model. We emply the so-called Schrödinger method to develop a model which is able to describe multi-streaming and therefore can serve as theoretical N-body double and replacement for the dust model.

June 2014

03.06.14 (Tuesday)
10:00, ESO room "Fornax", Star and Planet Formation Seminar
"Probing protoplanetary disk evolution with accretion measurements"
Carlo Felice Manara (ESO)
Abstract
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"Probing protoplanetary disk evolution with accretion measurements"

Carlo Felice Manara (ESO)

Abstract
Planet formation happens in evolving protoplanetary disks surrounding forming stars. The interaction between the star and the disk in the early phases of evolution puts strong constraint on the capability of such systems to form planets. This interaction happens mainly through accretion of matter from the disk onto the star, and its most significant signatures are the continuum excess in the UV part of the spectrum and the presence of various emission lines. With the advent of the VLT/X-Shooter instrument, the excess emission in the UV due to accretion is being studied simultaneously with the signatures in the visible and in the near-infrared, finally giving a complete view of this phenomenon.

From the study of the accretion mechanism in objects located in nearby young stellar clusters we are able to understand the typical evolution of disks and its implication on the planet formation mechanisms. I will present the results obtained with the spectroscopic surveys carried out with the VLT/X-Shooter in many nearby young star clusters (e.g., Lupus, rho-Ophiuci, sigma-Ori) and aimed at studying objects with different stellar properties and at various stages of disk evolution, including the transitional disk phase.
12:30, ESO room "Fornax", Lunch Talk
"Detection of B-mode polarization at degree angular scales using BICEP2"
Denis Barkats (ESO - ALMA)
Abstract
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"Detection of B-mode polarization at degree angular scales using BICEP2"

Denis Barkats (ESO - ALMA)

Abstract
BICEP2 recently reported a detection of B-modes in the CMB polarization at degree angular scales. This B-mode pattern is widely interpreted as the likely signature from primordial gravitational waves, consistent with those predicted to arise in the first 10^-34 seconds of the history of the universe, stretched from quantum to classical scales by the exponential expansion of cosmic inflation.

BICEP2 is a CMB polarimeter that was specifically designed to search for the elusive signal from inflationary gravitational waves in the B-mode power spectra around l = 80. BICEP2 has accumulated 3 years of data from the South Pole from 2010 to 2012, integrating continuously on a low-foreground region of effective size 1% of the whole sky. I will describe the experimental strategy, tests for foreground and systematics contamination, and results in the map and power spectra. The reported B-mode spectrum is well fit by a lensed-LCDM plus tensor theoretical model with tensor/scalar ratio r = 0.20 +0.07 -0.05 with r = 0 is strongly disfavored.
04.06.14 (Wednesday)
16:30, Cluster building Boltzmannstr. 2, Universe Colloquium
"Geometry from quantization: a simple overview"
Michael Kay (LMU)
Abstract
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"Geometry from quantization: a simple overview"

Michael Kay (LMU)

Abstract
Michael will outline the fundamentals of quantization of classical phase spaces. Subsequently, he will touch upon some specific roles quantization plays for the structure of string theory vacua.
05.06.14 (Thursday)
16:15, ESO auditorium "Telescopium", Munich Joint Astronomy Colloquium
"The structure of the Universe in the last 1Gyr"
Adi Nusser (Technion, Haifa, Israel)
Abstract
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"The structure of the Universe in the last 1Gyr"

Adi Nusser (Technion, Haifa, Israel)

Abstract
Analysts of the low-z observations of the Universe are fortunate: a. The late-time large scale structure is traced by "softly" evolving mature galaxies. This cosmic coincidence greatly simplifies the relation between galaxies and the dark matter. b. In addition to traditional galaxy redshift surveys, good quality measurements of peculiar motions of galaxies are now availalbe. A critical assessment of the observed large scale structure will be presented, starting from the Local Group of galaxies within 5 Mpc, out to z 0.1. Traditional and new probes will be shown to support the standard paradigm of structure formation, but not without raising a few eyebrows. Mild tweaks will be discussed as well as potential constraints on alternative theories of gravity.
12.06.14 (Thursday)
16:15, ESO New auditorium "Eridanus", Munich Joint Astronomy Colloquium
"Presupernova evolution, explosion and nucleosynthesis of rotating massive stars at various metallicities"
Marco Limongi (INAF - Rome Observatory)
Download (FLV) | Watch video / abstract
17.06.14 (Tuesday)
10:00, ESO room "Tucana", Star and Planet Formation Seminar
"The importance of spin-state chemistry in star formation"
Paola Caselli (MPE)
Abstract
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"The importance of spin-state chemistry in star formation"

Paola Caselli (MPE)

Abstract

Molecules are unique tools to study the dynamical and chemical evolution of interstellar clouds and star forming regions. A detailed understanding of the chemical processes is needed to exploit the data fully. I shall review some recent observational and theoretical work on dense cloud cores, pointing out the importance of spin-state chemistry to unveil crucial parameters such as the ionization fraction and the cloud age.
17.06.14 (Tuesday)
12:30, ESO auditorium "Telescopium", Lunch Talk
"Experimental Investigations of Molecule Formation on Surfaces of Astrophysical Interest"
Valerio Pirronello (University of Catania)
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"Experimental Investigations of Molecule Formation on Surfaces of Astrophysical Interest"

Valerio Pirronello (University of Catania)

Abstract
The abundance of most of the molecules observed in interstellar clouds can be explained by chemical reactions occurring in the gas phase; however some key species, like for instance H2 (the most important molecule in the Universe) and CO2 , cannot be formed efficiently enough by gas phase reactions. Their abundance can be understood when reactions occurring on the surface of interstellar grains (that act as catalysts) are taken into account. Furthermore several other species (like for instance water, formaldehyde, methanol and so on), for which gas phase formation routes do exist, are synthesized more efficiently on grain surfaces.

Surface reactions have been for long neglected or taken into account only on a theoretical ground, while due to intrinsic difficulties experimental investigations, in conditions and on solids that can be considered realistic analogues of interstellar grains, started to be tackled only rather recently.

In this talk I will present together with some well consolidated results on the formation of molecular hydrogen, that we started to study in the nineties, also some very recent and interesting results on other important species.
23.06.14 (Monday)
12:30, ESO room "Fornax", Lunch Talk
"Measuring Ho and Weighing Supermassive Black Holes with H2O Megamasers"
Jim Braatz (NRAO)
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"Measuring Ho and Weighing Supermassive Black Holes with H2O Megamasers"

Jim Braatz (NRAO)

Abstract
Water vapor masers have been detected in over 150 galaxies. In at least 25% of these galaxies, the masers are arranged in thin, sub-parsec disks orbiting the central supermassive black holes in AGNs. Maser disks can be mapped with VLBI, and in fact they provide the only means of mapping gas in AGNs on such scales, directly. So far, twenty have been mapped. The masers trace Keplerian orbits about the nucleus, and provide gold-standard masses of the central black holes. In several cases, they can be used to measure the distance to the host galaxy, geometrically. The Megamaser Cosmology Project (MCP) focuses on discovering such maser disks and using them to measure galaxy distances, and hence the Hubble Constant. The MCP is playing a critical role in resolving the apparent discrepancy between standard-candle based measurements of H0 and the value predicted by Planck measurements of the CMB.
24.06.14 (Tuesday)
12:30, ESO room "Fornax", Lunch Talk
"The SkyMapper Telescope and Survey"
Christian Wolf (RSAA, Mt Stromlo Observatory, Australian National University)
Abstract
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"The SkyMapper Telescope and Survey"

Christian Wolf (RSAA, Mt Stromlo Observatory, Australian National University)

Abstract
After a lengthy commissioning period, the SkyMapper telescope at Siding Springs Observatory in Australia has finally started its eponymous survey in March 2014. I will present the updated survey plans including its various components, an outlook to the science pursued including first results and the anticipated timeline for finishing the survey and worldwide access to the data.
25.06.14 (Wednesday)
16:30, Cluster building Boltzmannstr. 2, Universe Colloquium
"Accreting Magnetars"
Wei Wang (Nat. Astron. Observatory, China)
26.06.14 (Thursday)
16:15, ESO auditorium "Telescopium", Munich Joint Astronomy Colloquium
"Regulation of Star Formation in the Molecular Gas Disks of Spiral Galaxies"
Eva Schinnerer (MPIA, Heidelberg)
Download (FLV) | Watch video / abstract

July 2014

01.07.14 (Tuesday)
10:00, ESO room "Tucana", Star and Planet Formation Seminar
"Protoplanetary disks masses from CO isotopologues line emission"
Anna Miotello (MPE)
Abstract
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"Protoplanetary disks masses from CO isotopologues line emission"

Anna Miotello (MPE)

Abstract

An accurate measurement of disk masses is a key point for the understanding of disks evolution all the way up to planet formation. The disk mass is indeed the initial reservoir of material made available to build planets. So far, virtually all disk mass determinations are based on millimeter continuum observations of large dust grains. To derive the total gas + dust disk mass from these data involves however some assumptions on the dust opacity and the gas-to-dust ratio, usually taken to be 100 being gas the main disk constituent.

The alternative method for deriving disk masses relies on direct observations of the gas, whose bulk mass is in the outer cold (T~30K) regions. This zone can be well traced by sub-mm lines of CO. However, 12CO is not a good mass tracer because its lines become optically thick at the disk surface. Less abundant CO isotopologues such as 13CO, C18O and C17O have optically thin lines and as a consequence probe the gas down to the midplane. The total gas mass is then obtained with the isotopologue ratios taken to be constant at the isotope values found in the local ISM. This approach is however imprecise, because isotope selective processes are ignored and more detailed analysis should be carried out.

We properly treat the isotope-selective photodissociation, the main process controlling the abundances of CO isotopologues, for the first time in a full disk model (DALI, Bruderer et al. 2012). The chemistry, thermal balance, line and continuum radiative transfer are all considered together with a chemical network that treats 13CO, C18O, C17O, isotopes of all included atoms, and species, as independent species. Our results show that considering isotopologues ratios as constants leads to overestimate disk masses by up to one order of magnitude. Isotope selective processes indeed lead to regions where the isotopologues abundance ratio e.g. of C18O/12CO is considerably different from the atomic 18C/12C ratio.

The focus of our work is on the emission of the various isotopologues and their dependence on stellar and disk parameters, to set the framework for the analysis of ALMA data. We will employ ALMA to its full potential, only if we will have the correct tools to analyze its data.
02.07.14 (Wednesday)
16:30, Cluster building Boltzmannstr. 2, Universe Colloquium
"Recent and Future Results from Lattice QCD"
Andreas Kronfeld (Fermilab)
Abstract
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"Recent and Future Results from Lattice QCD"

Andreas Kronfeld (Fermilab)

Abstract
In this talk, Andreas will report on recent results from lattice QCD of broader interest. Most of these pertain to mesons and are useful for interpreting quark-flavor experiments. These highlight the recent progress well, and provide a basis for nucleon calculations of comparable quality. He will discuss how these calculations are becoming important in dark matter searches and neutrino scattering.
03.07.14 (Thursday)
12:30, Cluster building Boltzmannstr. 2, Fruits of the Universe series
"Seeing the Universe through lensing"
Stefan Hilbert (LMU/MPA)
Abstract
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"Seeing the Universe through lensing"

Stefan Hilbert (LMU/MPA)

Abstract
Gravitational lensing is the name astronomers give to the deflection of light from distant sources by the gravity of intervening matter structures, which can be stars, galaxies, or the whole large-scale structure. Stefan will give a brief introduction to strong and weak gravitational lensing, and how astronomers may use it to learn more about the matter and energy content of our Universe. He will discuss advantages of lensing, but also address some obstacles to overcome on the way to precision cosmology.
03.07.14 (Thursday)
16:15, ESO auditorium "Telescopium", Munich Joint Astronomy Colloquium
"Atomic and molecular gas properties of galaxies: constraints on galaxy formation models"
Guinevere Kauffmann (MPA)
Download (FLV) | Watch video / abstract
09.07.14 (Wednesday)
16:30, Cluster building, Boltzmannstr. 2, Universe Colloquium
"The motion of dark matter in phase space and indirect detection signals"
Francesc Ferrer (University of Washington)
Abstract
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"The motion of dark matter in phase space and indirect detection signals"

Francesc Ferrer (University of Washington)

Abstract
If dark matter (DM) has long-range interactions, the annihilation rate depends not only on the density profile, but also on its velocity distribution. Using phase-space considerations, we will discuss how the expectations for the indirect detection of DM in models with Sommerfeld enhancement can differ significantly from the standard estimate. In addition, the DM at the center of the Galaxy will be redistributed by the presence of the super-massive black hole. We will take a closer look at the DM profile in the vicinity of a black hole using a relativistic analysis, and discuss its implication for indirect searches of DM and tests of the black hole no-hair theorems.
10.07.14 (Thursday)
15:00, MPE Old Seminar Room, Special Universe Talk
"Quasar feedback in the form of powerful outflows: recent results and perspectives"
Marcella Brusa (University of Bologna)
Abstract
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"Quasar feedback in the form of powerful outflows: recent results and perspectives"

Marcella Brusa (University of Bologna)

Abstract
Quasar feedback on host galaxies in the form of powerful outflows is invoked as a key mechanism to quench star formation in massive galaxies, but direct observational evidences are still scarce and the debate on the physical origin of the observed outflows is still open. In this talk Marcella will review the observational constraints on the existence and origin of this mechanism, and present new X-shooter@VLT observations of a representative sample of 10 luminous, X-ray obscured QSOs at z~1.5 from the XMM-COSMOS survey, expected to be caught in the transitioning phase from starburst to AGN dominated systems. From the rest-frame optical spectra we could infer the presence of outflows in 6 out of 8 sources. This may be considered as a compelling indication that the color selection applied to our X-ray sample is effective in picking up objects in the outflowing phase. A comparison of the outflow energetic with the AGN luminosity and the kinetic energy associated to stellar processes, suggest that the AGN rather than the on-going star-formation may be the major driver for the presence of the observed broad and shifted components. In the two brightest sources we were also able to probe, via slit resolved spectroscopy, that the outflows extend up to 10 kpc scales. Most important, thanks to SINFONI data available for one of these 2 targets (XID2028) we were able to probe the presence of both positive and negative outflow-induced feedback in the host galaxy of the powerful QSO. Further perspective of studies with spatially resolved NIR spectroscopy and in the millimiter bands (e.g. ALMA, IRAM) to assess definitely the energetics of the outflows will also be discussed.
15.07.14 (Tuesday)
10:00, ESO room Tucana, Star and Planet Formation Seminar
"The dependence of star formation efficiency on gas density"
Andreas Burkert (LMU)
Abstract
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"The dependence of star formation efficiency on gas density"

Andreas Burkert (LMU)

Abstract
Observations indicate that the efficiency of star formation is a strong function of gas density or gas surface density with the star formation efficiency approaching unity on the scales of molecular cloud cores. I will argue that these observations are very puzzling. They require that dense gas has to be replenished on timescales that are similar to local gravitational collapse and star formation timescale. Numerical simulations cannot reproduce these observations, indicating that some fundamental processes that regulate star formation are still very poorly understood.
15.07.14 (Tuesday)
12:30, ESO auditorium "Telescopium", Lunch Talk
"X-shooter and SINFONI reveal powerful outflows in X-ray luminous obscured QSOs"
Marcella Brusa (University of Bologna)
Abstract
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"X-shooter and SINFONI reveal powerful outflows in X-ray luminous obscured QSOs"

Marcella Brusa (University of Bologna)

Abstract
Quasar feedback on host galaxies in the form of powerful outflows is invoked as a key mechanism to quench star formation in massive galaxies, but direct observational evidences are still scarce and the debate on the physical origin of the observed outflows is still open. After reviewing the observational constraints we have so far on the existence and origin of this mechanism, I will present new X-shooter@VLT observations of a representative sample of 10 luminous, X-ray obscured QSOs at z~1.5 from the XMM-COSMOS survey, expected to be caught in the transitioning phase from starburst to AGN dominated systems. From the rest-frame optical spectra we could infer the presence of outflows in 6 out of 8 sources. This may be considered as a compelling indication that the color selection applied to our X-ray sample is effective in picking up objects in the outflowing phase. A comparison of the outflow energetic with the AGN luminosity and the kinetic energy associated to stellar processes, suggest that the AGN rather than the on-going star-formation may be the major driver for the presence of the observed broad and shifted components. In the two brightest sources we were also able to probe, via slit resolved spectroscopy, that the outflows extend up to 10 kpc scales. Most important, thanks to SINFONI data available for one of these 2 targets (XID2028) we were able to probe the presence of both negative and positive outflow-induced feedback in the host galaxy of the powerful QSO.
22.07.14 (Tuesday)
12:30, ESO room "Fornax", Lunch Talk
"Orion as a paradigm for star formation"
Nicola Da Rio (University of Florida)
Abstract
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"Orion as a paradigm for star formation"

Nicola Da Rio (University of Florida)

Abstract
Young stellar clusters and associations are the direct output of the star formation process, and therefore can provide useful clues on how the conversion of gas into stars takes place in space and time, and on several details of the physics involved. The Orion Nebula Cluster, the densest cluster within a large star forming complex, due to its vicinity and abundant young population has always been target of observational studies. I will describe my research on this region, focusing on the first accurate constraint of its age spread - which therefore tracks the duration of star formation - the substellar IMF, the accretion lifetimes, the structure and kinematics. In particular I will describe the first conclusive evidence that the system is expanding due to early gas removal.
29.07.14 (Tuesday)
12:30, ESO auditorium "Telescopium", Lunch Talk
"The dust budget crisis in high-redshift submillimetre galaxies"
Kate Rowlands (University of St. Andrews)
Abstract
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"The dust budget crisis in high-redshift submillimetre galaxies"

Kate Rowlands (University of St. Andrews)

Abstract
Dust emission is a sensitive probe of the ISM in galaxies. Previous surveys have found galaxies were significantly dustier at earlier times, but the cause of this evolution, and the origin of the dust, are hotly debated topics in astrophysics. Using panchromatic data from the UV to the submillimetre, I will explore the physical properties and SEDs of a sample of ~250μm rest-frame selected submillimetre galaxies (SMGs). I then compare the SMGs to dusty galaxies at low redshift selected from one of the largest extragalactic Herschel surveys, H-ATLAS. From SED analysis it is found that a large fraction of the dust luminosity in SMGs originates from star-forming regions, whereas at lower redshifts the dust luminosity is dominated by the diffuse ISM. At the same dust mass the SMGs are offset towards a higher star-formation rate compared to the low redshift H-ATLAS galaxies. This is not only due to the higher gas fraction in SMGs but also because they are undergoing a more efficient mode of star formation. I will also present the results of chemical evolution modelling to understand the origin of dust in SMGs. Even after accounting for dust produced by low mass stars and supernovae the deficit in the dust mass budget provides support to the hypothesis that higher supernova yields, and/or substantial grain growth in the interstellar medium are required in order for the predicted dust mass to match observations of SMGs.

August 2014

12.08.14 (Tuesday)
12:30, ESO room "Fornax", Lunch Talk
"What can narrow-line regions tell us about AGN and their host galaxies?"
Julia Scharwächter (Observatoire de Paris, LERMA)
Abstract
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"What can narrow-line regions tell us about AGN and their host galaxies?"

Julia Scharwächter (Observatoire de Paris, Lerma)

Abstract
The ionizing continuum emitted by AGN can photoionize gas in the host galaxies on scales of tens of parsecs to kiloparsecs. The AGN-ionized gas on these scales is called 'narrow-line region' (NLR), because the gas emission lines are narrow (typically ~200-500 km/s) compared to the lines emitted by the high-density, high-velocity 'broad-line' gas at ~0.1 pc from the AGN. Since the density in the NLR is sufficiently low, the spectrum shows prominent forbidden lines ranging from low to high ionization. Emission from the NLR can be used to probe the shape of the AGN ionizing continuum, gas conditions in the AGN environment, obscuration and AGN unification, as well as AGN feedback. I will give an overview of the picture that has emerged from observations of AGN NLRs. I will show recent results from our ongoing optical IFU studies of NLRs in Seyfert galaxies and discuss open questions.
14.08.14 (Thursday)
12:30, Cluster Building, Boltzmannstr. 2, Fruits of the Universe series
"Large-scale structures in bimetric gravity"
Malin Renneby (Chalmers University of Technology, Sweden)
Abstract
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"Large-scale structures in bimetric gravity"

Malin Renneby (Chalmers University of Technology, Sweden)

Abstract
One of the most prominent questions in modern cosmology is the origin of the accelerated expansion of the universe. A solution might lie in modifying gravity in the infrared by adding a small mass to its mediating particle. In recent years, massive gravity and its dynamical extension bimetric gravity have been shown to be classically consistent theories. This prompts for a phenomenological investigation of their predictions in cases already examined in general relativity, such as in spherically-symmetric geometries and on cosmological scales. In this talk, Malin will focus on aspects related to the evolution of large-scale structures through analysis of the bimetric equations of motion for linear perturbations.
19.08.14 (Tuesday)
12:30, ESO room "Fornax", Lunch Talk
"The probability density function in molecular gas"
Maria Cunningham (UNSW, Sydney)
Abstract
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"The probability density function in molecular gas"

Maria Cunningham (UNSW, Sydney)

Abstract
We have undertaken multi-molecular-line surveys of the G333 and Vela C molecular clouds, using the wide-band capabilities of the Mopra telescope. The data sets are being used to investigate the chemistry, kinematics and hierarchical structure of the interstellar medium. In this talk we discuss the probability density function distribution in a range of molecules tracing different critical densities. We show that the chemical and excitation differences between different molecules show up as differences in the PDF for each molecule. The interpretation of the differences in terms of the type of gas traced by different molecules, and how useful each is for tracing gravitationally bound gas and/or gas that is tracing the broader hierarchical structure is discussed.
26.08.14 (Tuesday)
12:30, ESO room "Fornax", Lunch Talk
"Rosetta: the European Space Agency's comet-chasing mission"
Mark McCaughrean (ESA)
Abstract
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"Rosetta: the European Space Agency's comet-chasing mission"

Mark McCaughrean (ESA)

Abstract
On 6 August, Rosetta successfully rendezvoused with Comet 67P/Churyumov-Gerasimenko at a distance of more than 400 million km from Earth, marking the beginning of its main science mission. For the first time, Rosetta will escort and study a comet in great detail and at close proximity as it evolves from now until perihelion in August 2015 and beyond, and will deploy a smaller lander, Philae, to the comet's surface in November this year.

I'll give an overview of the scientific goals of this unique mission, the journey taken to reach 67P/C-G, and what to expect over the coming months as the landing site is selected and Philae is deployed. I'll also give a flavour of the early science results from the mission. Finally, I'll discuss some of the successes and pitfalls of our substantial communications and outreach campaign for the mission.

September 2014

02.09.14 (Tuesday)
10:00, ESO room "Fornax", Star and Planet Formation seminar
"Physical characterization of brown dwarfs"
Elena Manjavacas (MPIA Heidelberg)
Abstract
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"Physical characterization of brown dwarfs"

Elena Manjavacas (MPIA Heidelberg)

Abstract
Brown dwarfs are substellar objects (M<75MJup) which do are not able to sustain H burning. During their evolution, they cool down, changing their effective temperature and their spectral types, and it is difficult to constrain masses and ages for brown dwarfs. Determining the initial mass function and the evolution for these substellar objects is therefore a challenging problem. During my PhD I addressed the problem of brown dwarf characterization in three different approaches: determining parallaxes of several T brown dwarfs, medium resolution VLT/ISAAC spectroscopy of young M-L brown dwarfs and searching for brown dwarf binaries using VLT/X-Shooter spectroscopy.
03.09.14 (Wednesday)
16:30, Cluster Building, Boltzmannstr. 2, Special Universe Talk
"New experimental results for the charged-pion polarisability from COMPASS"
Alexey Guskov (CERN)
Abstract
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"New experimental results for the charged-pion polarisability from COMPASS"

Alexey Guskov (CERN)

Abstract
Alexey will report on new results for the charged-pion polarisability from the COMPASS experiment at CERN.
09.09.14 (Tuesday)
10:00, ESO room "Fornax", Star and Planet Formation seminar
"Interstellar chemistry of nitrogen hydrides with Herschel"
Romane Le Gal (IPAG, Grenoble)
Abstract
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"Interstellar chemistry of nitrogen hydrides with Herschel"

Romane Le Gal (IPAG, Grenoble)

Abstract
Nitrogen is amongst the most abundant metals in the interstellar medium. Observations of several nitrogen-bearing species suggest abundances in sharp disagreement with current chemical models. Although some of these observations show that some gas-grain processes are at work, gas-phase chemistry needs first to be revisited. Strong constraints are provided by recent Herschel/HIFI observations of nitrogen hydrides fundamental rotational transitions in cold gas [1]. The aim of my PhD thesis work was to comprehensively analyse the interstellar chemistry of nitrogen, focussing on the gas-phase formation of the simplest polyatomic species, namely nitrogen hydrides. In cold and dense gas conditions, the chemistry of these latter is initiated by slow neutral-neutral reactions (the conversion from N to N2, in contrast to their carbonated and oxygenated analogues. We have investigated and revisited this specific part of the nitrogen chemistry. To this purpose, we present a new chemical network [2] in which the kinetic rates of critical reactions involved in nitrogen chemistry have been updated. Our new network is based on recent experimental and theoretical studies, including the calculation of nuclear spin branching ratios [3]. The different spin symmetries of the nitrogen hydrides are treated self-consistently, together with the ortho and para forms of molecular hydrogen. This new network is used to model the time evolution of the nitrogen species abundances in cold and dense gas conditions (n=10^4 cm^-3, T=10 K). The steady-state results are compared to observations of NH, NH2 and NH3 towards a sample of low-mass protostars, with a special emphasis on the influence of the overall amounts of gaseous carbon, oxygen, and sulphur. Our predicted ortho-to-para ratios for NH2 and NH3 [4] are also compared with the observational results of Persson et al. towards cold diffuse clouds [5].

References
[1] Hily-Blant, P., Maret, S., Bacmann, A., et al. 2010a, A&A, 521, L52
[2] Le Gal, R., Hily-Blant, P., Faure, A., Pineau des Forêts, G., Rist, C., & Maret, S., 2014, A&A, 562, A83
[3] Rist, C., Faure, A., Hily-Blant, P., & Le Gal, R., 2013, J. Phys. Chem. A, 117, 9800
[4] Faure, A., Hily-Blant, P., Le Gal, R., Rist, C., & Pineau des Forêts, G., 2013, ApJ, 770, L2
[5] Persson, C. M., De Luca, M., Mookerjea, B., et al. 2012, A&A, 543, A145
09.09.14 (Tuesday)
12:30, ESO room "Fornax", Lunch Talk
"Interstellar medium and initial stages of star formation: comparing simulations and observations"
Johanna Malinen (University of Helsinki)
Abstract
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"Interstellar medium and initial stages of star formation: comparing simulations and observations"

Johanna Malinen (University of Helsinki)

Abstract
Filamentary structures in interstellar molecular clouds have long been recognised as an important part of the star formation process. Recent studies have confirmed that dense cores in different stages of star formation are commonly located in the filaments. Therefore, it is important to study the structure and formation of the filaments and the cores, to understand the details of the early phases of star formation. The density structure of molecular clouds can be studied using many different methods and wavelengths. All techniques have their own drawbacks, and, therefore, it is crucial to compare the results obtained with different methods. Before making conclusions on observational data, the observational uncertainties and biases should be evaluated with simulations. In this presentation, I will give a short overview of star formation theory, observations, and simulations, and review the main results of my PhD thesis, concentrated on comparing simulations and observations of the early, prestellar phase of star formation.
15.09.14 (Monday)
12:30, ESO auditorium "Telescopium", Lunch Talk
"Oxygen in the Local Universe: Error and Uncertainty in Abundances"
Kevin Croxall (Ohio State University)
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"Oxygen in the Local Universe: Error and Uncertainty in Abundances"

Kevin Croxall (Ohio State University)

Abstract
The metal content of a galaxy is one of the most important properties used to distinguish between viable evolutionary scenarios and strongly influences many of the physical processes in the ISM. An absolute and robust calibration of extragalactic metallicities is essential in constraining models of chemical enrichment, chemical evolution, and the cycle of baryons in the cosmos. Despite this strong dependence on abundance, the calibration of nebular abundances from nebular emission lines remains uncertain. Different calibrations of the abundance scale require different assumptions, which may or may not be valid, and measurements, not all of which are easily obtained. MODS on LBT and the late Herschel Space Observatory are allowing us to clarify this long standing calibration uncertainty. The sensitivity of MODS is enabling the detection of numerous temperature sensitive lines and features in nearby galaxies and Herschel observations of the [O III] 88 micron fine structure line in nearby galaxies are enabling the determination of nebular abundances that are nearly independent of temperature. I will discuss current efforts at constraining the abundance scale using these modern facilities.
16.09.14 (Tuesday)
12:30, ESO auditorium "Telescopium", Lunch Talk
"Astrochemistry, cosmic rays, and H3+"
Miwa Goto (USM)
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"Astrochemistry, cosmic rays, and H3+"

Miwa Goto (USM)

Abstract
The talk starts with the introductory accounts of the astrochemistry, the cosmic rays and the hydrogen molecular ion H3+ to illustrate how the study of the one has immediate impacts on the other two. The Galactic Center is used as a laboratory to show that the three elements lively influence each other. The emphasis is put on how the spectroscopy of the H3+ has been used to develop our view of the interstellar medium in the Galactic Center in the past decade.
23.09.14 (Tuesday)
10:00, ESO room "Fornax", Star and Planet Formation seminar
"Galactic Cold Interstellar Filaments"
Ke Wang (ESO)
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"Galactic Cold Interstellar Filaments"

Ke Wang (ESO)

Abstract
The molecular ISM is known to be highly hierarchical and filamentary. Studies in recent years have demonstrated the importance of filaments in star formation, at scales of <10 pc and >100 pc, and suggest a new paradigm for star formation. However, extremely filamentary giant molecular clouds (GMCs) at scales between 10 and 100 pc have not been studied systematically. A compelling sample does not exist at the first place, due to a historical limitation in the identifying methodology (i.e., extinction).
We recently launched a dedicated project to bypass this limitation, using the full Hi-GAL images to directly search for large filaments in the entire Galactic plane. As a pilot study of the project, we select a sample of 9 most prominent filaments with a length of 30-103 pc and mass (2.4-19)x10^4 Msun. These filaments are cold compared to surroundings and show no significant internal heating. This makes our project unique in probing the early evolutionary phases to study the connection of filamentary GMCs to the onset of star formation. I will present preliminary analysis of the pilot sample.
23.09.14 (Tuesday)
12:30, ESO room "Fornax", Lunch Talk
"AKARI FIR All-Sky Maps"
Yasuo Doi (University of Tokyo)
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"AKARI FIR All-Sky Maps"

Yasuo Doi (University of Tokyo)

Abstract
We present the AKARI far-infred (FIR) all-sky maps and describe its characteristics, calibration accuracy and scientific capabilities. The AKARI FIR survey has covered 97% of the whole sky in four photometric bands, which cover continuously 50--180 micron with band central wavelengths of 65, 90, 140, and 160 microns. The spatial resolution of the maps is ~60--90 arcsecs and the detection limit is ~1--12 [MJy/sr] with an absolute accuracy of ~20%.

The data for the first time reveal the whole sky distribution of interstellar matter with arcminute-scale spatial resolutions at the peak of dust continuum emission, enabling us to investigate large-scale distribution of interstellar medium in great detail. The filamentary structure covering the whole sky is well traced by the all-sky maps.

The data are currently under assessment by the AKARI science team members and to be publicly released later this year. The release schedule is also described in this presentation.
30.09.14 (Tuesday)
12:30, ESO auditorium "Telescopium", Lunch Talk
"Modelling Galaxies within state-of-the-art Cosmological Simulations"
Violeta Gonzalez-Perez (University of Durham)
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"Modelling Galaxies within state-of-the-art Cosmological Simulations"

Violeta Gonzalez-Perez (University of Durham)

Abstract
Galaxies are thought to form within haloes of dark matter, whose gravity allows the galaxies to exist. The formation and evolution of galaxies is affected by a multitude of other processes besides gravity and computational modelling is the only way we can attempt to understand all these processes. In this work we present a new development of the GALFORM semi-analytical model of galaxy formation and evolution, which exploits a Millennium Simulation-class N-body run performed with the Wilkinson Microwave Anisotropy Probe 7 cosmology. We use this new model to study the impact of the choice of stellar population synthesis (SPS) model on the predicted evolution of the galaxy luminosity function. Besides this model, we have generated a new GALFORM flavour constructed from merger trees derived from EAGLE, a hydrodynamical simulation. We compare results from both GALFORM and EAGLE.

October 2014

02.10.14 (Thursday)
14:00 - 17:30, ESO room "Fornax"
SPHERE/ESO Mini Workshop
(via video link from ESO Santiago)
Agenda:
14:00 - 15:00 : Overview of the instrument
15:00 - 15:30 : Operations with extreme AO, SAXO
15:30 - 16:00 : break
16:00 - 17:30 : Science cases, strengths + limitations, SPHERE or NACO?
02.10.14 (Thursday)
16:15, ESO auditorium "Telescopium", Munich Joint Astronomy Colloquium
"Recombination and Relativistic Effects in Shock Breakouts and Cooling Envelopes: Supernovae and Low Luminosity Gamma Ray Bursts"
Re'em Sari (Racah Institute of Physics, the Hebrew University, Jerusalem)
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"Recombination and Relativistic Effects in Shock Breakouts and Cooling Envelopes: Supernovae and Low Luminosity Gamma Ray Bursts"

Re'em Sari (Racah Institute of Physics, the Hebrew University, Jerusalem)

Abstract
Stellar explosions in Supernovae or Gamma Ray Bursts begin with the launching of a shock into the stellar envelope. As the shock wave propagates towards the edge of the star, the decreasing density causes the shock to accelerate, and eventually break out of the star. We show that for fast shocks, with v>10,000km/s, the radiation is out of equilibrium causing the breakout to appear in x-rays rather than the previously estimated UV. Later, recombination in the cooling expanding envelope may lead to the flat lightcurve of type-IIp supernovae. Finally, we argue, that relativistic effects in extreme breakouts may be the sources of low luminosity Gamma Ray Bursts, and show that their properties match well with our theory.
07.10.14 (Tuesday)
10:00, ESO room "Fornax", Star and Planet Formation Seminar
"Accretion and stellar magnetism in T Tauri stars"
Gaitee Hussain (ESO)
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"Accretion and stellar magnetism in T Tauri stars"

Gaitee Hussain (ESO)

Abstract
Magnetic field maps of about a dozen accreting T Tauri stars have now been obtained using the technique of Zeeman Doppler imaging. I will give an overview of what we've learnt about the magnetic fields on these stars and a possible relationship between accretion, rotation and the large scale magnetic fields in classical T Tauri stars. I will then present results from a new study focussing on the wTTS, Lkca 4, which suggests the picture of stellar magnetism might fundamentally change in stars that are no longer accreting.
08.10.14 (Wednesday)
16:30, Cluster building, Boltzmannstr. 2, Universe Colloquium
"Fatal fate: A gas cloud on its way to the massive black hole in the Galactic Center"
Stefan Gillessen (MPE)
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"Fatal fate: A gas cloud on its way to the massive black hole in the Galactic Center"

Stefan Gillessen (MPE)

Abstract
The Galactic Center is a unique astrophysical laboratory. Due to its proximity, we can observe in unparalleled detail the interaction of the massive black hole with its stellar and gaseous environment. In 2011, we discovered a compact gas cloud ("G2") with roughly 3 Earth masses that is falling on a near-radial orbit toward the massive black hole, with a pericenter passage in 2014. Our 10-year data set beautifully shows that G2 gets tidally sheared apart due to the massive black hole's force. We expect that in addition to the tidal effects, hydrodynamics will get important in the coming years, as G2 collides with the hot ambient gas around Sgr A*. Simulations show that ultimately, the cloud's material will fall into the massive black hole. Predictions for the accretion rate and luminosity evolution, however, are very difficult due to the many unknowns. Nevertheless, this might be a unique opportunity in the next years to observe how gas feeds a massive black hole in a galactic nucleus.
09.10.14 (Thursday)
16:15, ESO auditorium "Telescopium", Munich Joint Astronomy Colloquium
"Fundamental Physics and Astrophysics Problems Around the Birth and Death of Neutron Stars"
Thomas Janka (Max-Planck-Institut für Astrophysik)
Download (FLV) | Watch video / abstract
14.10.14 (Tuesday)
11:30, MIAPP building, seminar room, Special Universe Colloquium
"Neutrinos and the Standard Model"
Samuel M. Bilenky (Joint Inst. for Nuclear Research, Dubna, Russia)
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"Neutrinos and the Standard Model"

Samuel M. Bilenky (Joint Inst. for Nuclear Research, Dubna, Russia)

Abstract
In the first part of the talk the basics of neutrino masses and mixing and the phenomenological status of neutrino oscillations will be discussed . In the second part the special role of neutrinos in the Standard Model and the most economical possibility for neutrinos to be massive and mixed will be considered.
14.10.14 (Tuesday)
12:30, ESO room "Fornax", Lunch Talk
"The origin of free-floating planets and brown dwarfs"
Viki Joergens (MPIA Heidelberg)
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"The origin of free-floating planets and brown dwarfs"

Viki Joergens (MPIA Heidelberg)

Abstract
Free-floating substellar objects are the link between stars and planets. They play a key role for our understanding of star and planet formation and of cool planetary-like atmospheres. After reviewing aspects of their physics, detection history, and formation, I will present observations of young brown dwarfs and free-floating planets. This includes a precise radial velocity survey for companions at the VLT, Herschel studies of disks, accretion studies, and spectro-astrometric detections of outflows. I will present our recent result that the coolest known object that is formed in a star-like mode is a free-floating planet. We discovered significant accretion (VLT/SINFONI) and a substantial disk (Herschel) of the young 12 Jupiter mass object OTS44 (M9.5). This demonstrates that the processes that characterize the canonical star-like mode of formation apply to isolated objects down to a few Jupiter masses. Our results suggest that the increasing number of young free-floating planets and ultra-cool field T and Y dwarfs are the low-mass extension of the stellar population.
16.10.14 (Thursday)
16:15, ESO auditorium "Telescopium", Munich Joint Astronomy Colloquium
"The importance of radio-AGN feedback in massive galaxy formation: Insights from the COSMOS survey"
Vernesa Smolcic (University of Zagreb)
Download (FLV) | Watch video / abstract
21.10.14 (Tuesday)
12:30, ESO room "Fornax", Lunch Talk
"Brightest Cluster Galaxies as probes of galaxy formation"
Paola Oliva (Swinburne University, Australia)
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"Brightest Cluster Galaxies as probes of galaxy formation"

Paola Oliva (Swinburne University, Australia)

Abstract
Brightest group and cluster galaxies (BGGs/BCGs) are old giant ellipticals, which have been shown to be different from any other cluster galaxy. Despite of being easy detectable their formation and evolution is still poorly understood. I will present a statistical analysis of a large sample of 883 Brightest group and cluster galaxies (BGGs/BCGs) from the Galaxy and Mass Assembly Survey (GAMA). We analyse their stellar mass growth, position in the cluster, and the percentage of BGGs/BCGs that show H\alpha in emission. We find that BCGs grow steeply until z~0.5, and slow down at lower redshift.

BCGs have been predicted to have a more active accretion history than less massive galaxies. We further use IFU spectroscopy to study the spatially-resolved stellar populations of BCGs and their connection with galaxy's angular momentum. We find that all the BCGs in our sample have gone through at least one major merger after z=1. Our stellar population analysis suggest that BCGs have a more active accretion history than early-type galaxies of similar mass.
22.10.14 (Wednesday)
16:30, Cluster building, Boltzmannstr. 2, Universe Colloquium
"Prospects in Hadron Spectroscopy"
Vincent Mathieu (Indiana Univ., USA; Cluster guest)
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"Brightest Prospects in Hadron Spectroscopy"

Vincent Mathieu (Indiana Univ., USA; Cluster guest)

Abstract
There are several experiments in Europe (COMPASS, LHCb), USA (CLAS, GlueX) and Asia (BES, Belle) devoted to hadron spectroscopy. In this talk, their goals and prospects are presented with a special emphasis on the discovery of new 'exotic' resonances. There are indeed indications from these experiments about resonances (hybrid mesons, glueballs, tetraquarks, etc.) beyond the quark model classification. However, a close collaboration between theorists and experimentalists is necessary to draw robust conclusions about their existence. Vincent will review the theoretical developments necessary to fully exploit the data provided by the experiments and finally reach their objectives.
23.10.14 (Thursday)
12:30, Cluster building, Boltzmannstr. 2, Fruits of the Universe series
"Discovering High-Energy Astrophysical Neutrinos with IceCube"
Claudio Kopper (University of Alberta; Cluster guest)
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"Discovering High-Energy Astrophysical Neutrinos with IceCube"

Claudio Kopper (University of Alberta; Cluster guest)

Abstract
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23.10.14 (Thursday)
16:15, ESO auditorium "Eridanus", Munich Joint Astronomy Colloquium
"What drives the evolution of the Milky Way's disk?"
Jo Bovy (IAS, Princeton)
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"What drives the evolution of the Milky Way's disk?"

Jo Bovy (IAS, Princeton)

Abstract
Observations of the structure and dynamics of different stellar populations in the Milky Way's disk provide a unique perspective on disk formation, evolution, and dynamics. I will review our current knowledge of the chemo-orbital structure of the disk. I will then discuss new measurements of the kinematics and chemistry of intermediate-age stars over a large part of the Galactic disk from the APOGEE survey and the new insights these measurements provide about the formation and evolution of the disk.
27.10.14 (Monday)
11:00, MIAPP building, Lecture Hall,
Cosmic Chemical Evolution - Cluster Lectures / Part 1
"Overview"
Nikos Prantzos (IAP Paris / Cluster guest)
28.10.14 Tuesday)
11:00, MIAPP building, Lecture Hall,
Cosmic Chemical Evolution - Cluster Lectures / Part 2
"A (not so simple) case study: the Solar neighborhood"
Nikos Prantzos (IAP Paris / Cluster guest)
28.10.14 (Tuesday)
12:30, ESO auditorium "Telescopium", Lunch Talk
"Shed Light on the Properties of the Circum/Inter-galactic Gas"
Fabrizio Arrigoni (MPIA Heidelberg)
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"Shed Light on the Properties of the Circum/Inter-galactic Gas"

Fabrizio Arrigoni (MPIA Heidelberg)

Abstract
Giant (100 kpc) and luminous Lyman-alpha nebulae are observed at high redshift around high-redshift radio galaxies (HZRGs), QSOs, and in a population known as Lyman-alpha blob (LABs). There is a growing body of evidence that all of these phenomenon are somehow related, although the mechanism powering their emission is poorly understood. I will present the first results of an ongoing narrow-band imaging survey for diffuse Ly-alpha emission around z ~ 2 quasars, including the discovery of two of the largest Ly-a nebulae known, with emission extending out to ~ 500 kpc into the cosmic web. Observations of high-ionization emission lines like HeII (1640A) and CIV (1549A) provide important diagnostics of physical conditions in these nebulae, and clues to the mechanism that power them. I will present sensitive observations of these emission lines, for a giant Ly-a nebula around a quasar, as well as from deep observations of a sample of 13 Ly-alpha blobs. I will show how photoionization models can be used to interpret such observations. Future deep observations with VLT/MUSE will revolutionize the study of such nebulae, allowing the detection of multiple diagnostic lines, which will provide important constraints on the physical nature of circum/inter-galactic gas.
29.10.14 (Wednesday)
11:00, MIAPP building, Lecture Hall,
Cosmic Chemical Evolution - Cluster Lectures / Part 3
"The Milky Way halo"
Nikos Prantzos (IAP Paris / Cluster guest)
29.10.14 (Wednesday)
16:30, Cluster building, Boltzmannstr. 2, Universe Colloquium
"Particle Physics meets Astrophysics: Astrophysical counterparts of IceCube neutrinos""
Elisa Resconi (TUM) and Paolo Padovani (ESO)
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"Particle Physics meets Astrophysics: Astrophysical counterparts of IceCube neutrinos""

Elisa Resconi (TUM) and Paolo Padovani (ESO)

Abstract
IceCube has recently reported the discovery of high-energy neutrinos of astrophysical origin, opening up the PeV (10^15 eV) sky. These observations are challenging to interpret on the astronomical side and have triggered a fruitful intra-cluster collaboration across particle and astro-physics. Elisa (TUM) and Paolo (ESO) will first describe the IceCube experiment and then, by using positional and energetic diagnostics, discuss plausible astronomical counterparts to the neutrino events. These include extragalactic sources, namely BL Lacertae objects, a sub-class of blazars, and Galactic pulsar wind nebulae. They will conclude by addressing the implications of our results and possible ways forward.
30.10.14 (Thursday)
11:00, MIAPP building, Lecture Hall,
Cosmic Chemical Evolution - Cluster Lectures / Part 4
"Lightweights and Heavyweights"
Nikos Prantzos (IAP Paris / Cluster guest)
30.10.14 (Thursday)
11:10, ESO Library, AGN Club
"The influence of bars on AGN fueling over the last 7 billion years"
Mauricio Cisternas (IAC Tenerife, Spain)
30.10.14 (Thursday)
16:15, ESO auditorium "Telescopium", Munich Joint Astronomy Colloquium
"Exploring Strong Gravity in the Galactic Center"
Jason Dexter (MPE)
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"Exploring Strong Gravity in the Galactic Center"

Jason Dexter (MPE)

Abstract
The Galactic center black hole, Sgr A*, provides a remarkable opportunity to study strong gravity using either orbiting stars or accreting gas. Very long baseline interferometry observations at millimeter wavelengths are now spatially resolving event horizon scales around Sgr A*, and near-infrared astrometry with the VLTI instrument GRAVITY will achieve similar resolution in the next few years. In both cases, interpreting the data requires physical modeling. I will discuss the construction of relativistic emission models from numerical simulations of black hole accretion flows and jets, what we've learned from their comparison with current data, and the prospects for detecting signatures of strong gravity (e.g., the black hole "shadow") in future observations. I will also argue that the recent discovery of a rare magnetar outburst near Sgr A* implies the presence of an unusual pulsar population in the Galactic center.