Seminars and Colloquia at ESO Garching and on the campus

April 2019

16/04/19 (Tuesday)
16:15, MPP, Freimann, Munich | ESO Garching
MPP Kolloquium
Talk — Low-mass dileptons: A thermometer for the hottest stuff in the universe
Torsten Dahms (TUM)
15:15, Auditorium Eridanus (ESO HQE, Garching) | ESO Garching
Special Colloquium
Talk — Imaging Black Holes - First Results from the Event Horizon Telescope
Heino Falcke (Radboud University Nijmegen)
10:00, Fornax (ESO HQ, Garching) | ESO Garching
Star and Planet Formation Seminar
Talk — Flying a telescope: the BLAST-TNG experiment
Gabriele Coppi (University of Pennsylvania)

Abstract

BLAST-TNG is a long-duration, high altitude, balloon-borne telescope scheduled to fly in the 2019-2020 season from Antarctica. The data from the 28 day flight will provide new insight into the properties of dust and the role of magnetic fields and its role in the star formation process. BLAST-TNG will observe the sky at three difference wavelength, 250um 350um and 500um, with more than 3000 polarization sensitive KIDs (Kinetic Inductance Detectors) cooled at 270mK.

15/04/19 (Monday)
15:30, MPA Large Seminar Room E.0.11 (MPA, Garching) | ESO Garching
MPA Institute Seminar
Talk — Cosmic gas flows and the distribution of heavy elements in and around galaxies
Freeke van de Voort (MPA)
12/04/19 (Friday)
15:30, MPA Old Lecture Hall 401 | ESO Garching
High Energy Seminar
Talk — Merger Shocks in Galaxy Clusters - from Bow Shocks to Runaway Shocks
Congyao Zhang (MPA)
14:00, Library (ESO HQ, Garching) | ESO Garching
Stellar Coffee and Planetary Tea
Talk — The role of cluster age on the onset of multiple populations in stellar clusters
Silvia Martocchia (ESO)

Abstract

It is now well established that globular clusters (GCs) host unusual chemical patterns in the form of star-to-star abundance variations in light elements. However, the origin of such multiple stellar populations (MPs) is still far from being understood. The detailed characterisation of MPs is fundamental in our understanding of GC formation, which in turn has consequences for the formation and evolution of galaxies. To this purpose, we have undertaken an HST photometric survey of 13 star clusters in the Magellanic Clouds (MCs) with masses comparable to that of old GCs where MPs have been identified, but with significantly younger ages (from 1.5 - 11 Gyr). We found that the extent of the MPs (in both chemical spread and in the number of stars that show the chemical anomaly) are a strong function of age, with older clusters having more extreme populations. Another surprising result is that we find MPs down to ~2 Gyr old clusters for the first time. This is fundamental as it shows that the formation of MPs is not restricted only to the early Universe, but it continued down to a redshift of at least z=0.17.  This provides another strong link between young massive clusters and the ancient globular clusters, suggesting a common formation/evolution mechanism.  The results presented here represent fundamental constraints for the origin of MPs and might point towards a new and fresh direction into the onset of this complex phenomenon.

11/04/19 (Thursday)
15:15, Auditorium Eridanus (ESO HQE, Garching) | ESO Garching
Munich Joint Astronomy Colloquium
Talk — Quasar-driven winds in galaxy formation
Nadia Zakamska (Johns Hopkins University)
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Abstract

Quasars are now thought to have made critical impact on galaxy formation. Feedback from accretion onto supermassive black holes is frequently implicated in establishing the black hole mass vs galaxy bulge correlations and in limiting the maximal mass of galaxies. In this talk, I will review the indirect evidence for quasar feedback as required by galaxy formation models. I will then review the recent progress on detecting direct evidence for quasar-driven outflows and other types of feedback through multi-wavelength observations. These data may provide direct observational evidence for one of the long-standing paradigms in galaxy formation.

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11:10, Library (ESO HQ, Garching) | ESO Garching
AGN Club
Talk — Predictions of the Pseudo-Complex Theory of Gravity for EHT Observations: Observational Tests
Thomas Boller (MPE)
10/04/19 (Wednesday)
10:45, Library (ESO HQ, Garching) | ESO Garching
Informal Discussion
Talk — How much does the Milky Weigh?
Laura Watkins (ESO)

Abstract

The mass of the Milky Way is one of its most fundamental properties, important for understanding the MW itself, the past and future of the Local Group of galaxies, and where the MW sits in a cosmological context. Yet mass estimates in the literature are significantly scattered and many estimates differ by more than their uncertainties. Mass estimates rely on accurately measuring total velocities of objects within the MW, but historically we have only been able to measure one component of motion, leaving two components unknown. However, this has changed thanks to recent proper motion measurements from HST and Gaia. I will talk about why knowing the mass of the MW is so important, how we can measure it, why there has been such disagreement in the past, and how recent HST and Gaia measurements are finally bringing better agreement.

09/04/19 (Tuesday)
16:15, MPP, Freimann, Munich | ESO Garching
MPP Kolloquium
Talk — Precision at the LHC: why and how
Giulia Zanderighi (MPP)
12:00, Library (ESO HQ, Garching) | ESO Garching
Lunch Talk
Talk — Using sub-millimeter surveys to look for proto-brown dwarf candidates
Oscar Morata (currently ESO visitor)

Abstract

Brown dwarfs (BDs) bridge the mass range between low-mass stars and Jupiter-like planets. BDs are relatively abundant in star forming regions and in the field, but their formation mechanism is still under debate.  Some theoretical descriptions and observational findings support the idea that stars and BDs share a common formation history, but the observational evidence is still not enough to distinguish the competing formation models. The study of the earliest phases of BD formation, the proto-BD phase, when they are still embedded in the parental cloud, and finding BDs formed in isolation with similar properties to low-mass stars would strongly support the star-like scenario as the primary formation mechanism. Our group started more than ten years a project to search and characterize very young proto-BD through a systematic and multi-wavelength exploration in nearby star-forming regions. I will show some of the results of the collaboration that has found a few tens of candidate proto-BDs in Taurus, Barnard 30, and Chamaeleon II, which begin to point out to the formation of BDs as a scaled-down version of low-mass stars.

08/04/19 (Monday)
15:30, MPA Large Seminar Room E.0.11 (MPA, Garching) | ESO Garching
MPA Institute Seminar
Talk — Characterizing the circum/inter-galactic medium in emission around z~3 quasars
Fabrizio Arrigoni Battaia (MPA)
10:45, Library (ESO HQ, Garching) | ESO Garching
KES: Knowledge Exchange Series
Talk — Explosive Nucleosynthesis in Core Collapse Supernovae
Marco Limongi (INAF, Osservatorio Astronomico di Roma)

Abstract

Core Collapse Supernovae are the endpoint of the evolution of massive stars (M > 10 Msun). They play a fundamental role in the evolution of the Universe because, among the other things, contribute to the production of most of the elements (especially those necessary to life), induce star formation when the shock wave following the explosion passes though the interstellar medium, produce neutron stars and black holes, are connected to the GRB events (some of them) and last, but not least, are one of the sources of gravitational waves. Therefore, a good knowledge of these events are needed to shed light on many astrophysical topical subjects.

In this lecture I will mainly focus on the role of core collapse supernovae in then chemical evolution of the matter and, in particular, on the nucleosynthesis occurring during the explosion. I will describe the basic principles of the nuclear burning at high temperatures coupled to the dynamics of the exploding mantle of the star and will show the main products of the various explosive burning.

For sake of completeness I will also briefly discuss the chemical composition of the final ejecta, how it depends on the progenitor star and on the remnant mass. Finally, I will show which is the contribution of a generation of massive stars (i.e., core collapse supernovae) to the global enrichment of the interstellar medium.

04/04/19 (Thursday)
15:15, Auditorium Eridanus (ESO HQE, Garching) | ESO Garching
Munich Joint Astronomy Colloquium
Talk — Neutral and molecular gas outflows as tracers of the impact of radio jets
Raffaella Morganti (ASTRON, the Netherlands Institute for Radio Astronomy & Kapteyn Astronomical Institute, University of Groningen)
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Abstract

Our view of the gas and its physical conditions in the central region of AGN has been enriched by the discover of fast and massive outflows of HI and molecular gas. These outflows can be driven by radiation/winds but also by the interaction of the radio plasma with the ISM. Understanding the origin and quantifying their impact requires to trace their location and derive their physical conditions (density of the gas, mass, mass outflow rate and kinetic energy of the outflow etc.). Particularly interesting has been the finding that in the first phase of their life, jet in radio galaxies can be particularly effective in driving such outflows. This crucial phase is at the heart of the idea of feedback, therefore particularly relevant for studying feedback in action.

In this talk, I will present some of the results we have obtained to trace jet-driven HI and molecular gas outflows down to scales ranging from hundred to tens of pc. The impact of low-power radio jets will be discussed and the comparison with the predictions from numerical simulations will also be presented. Outflows of up to 100 Msun/yr have been found in molecular gas using ALMA while the HI observed with VLBI is showing that the outflowing gas is clumpy as also predicted from numerical simulations. I will describe the kinematics of the gas and its conditions and the relevance they may have for feedback.

 

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11:00, MPA Large Seminar Room E.0.11 (MPA, Garching) | ESO Garching
Cosmology Seminar
Talk — Splitting growth and geometry to test LCDM with the Dark Energy Survey
Jessie Muir (Stanford Univ.)
03/04/19 (Wednesday)
10:45, Library (ESO HQ, Garching) | ESO Garching
Informal Discussion
Talk — Signatures of multi-phase AGN-driven outflows in optical spectra
Michele Perna (INAF, Osservatorio Astrofisico di Arcetri)

Abstract

Numerous models of galaxy evolution expect that AGN should have a negative feedback effect on star formation in their host galaxy, by injecting energy into the ISM in the form of powerful outflows. In this informal discussion, I will focus on observational evidence of multi-phase outflows in optical spectra of nearby AGN. In particular, I will show which are the best tracers of ionised and atomic outflows among emission and absorption lines commonly observed in optical spectra. Then, I will talk about general outflow properties and their connection with AGN activity. In the last part, I will discuss gas mass outflow rate and related energetics, generally used to estimate the feedback impact on galaxy evolution.

02/04/19 (Tuesday)
12:00, Library (ESO HQ, Garching) | ESO Garching
Lunch Talk
Talk — The Age Distribution of the Milky Way's halo: A Storyteller of Galaxy Formation
Daniela Carollo (INAF, L' Osservatorio Astrofisico di Torino)

Abstract

The halo system of the Milky Way is a precious laboratory because it provides unique elemental abundances and kinematic information on the first objects formed in the Universe and encoded in the ancient stars that populate this complex structure. All this information can be used to tightly constrain models of galaxy formation and evolution. In this talk, I will focus on the age distribution and age gradients in the halo system and I will discuss possible formation scenarios of the Galaxy based on these results.

10:00, Fornax (ESO HQ, Garching) | ESO Garching
Star and Planet Formation Seminar
Talk — (topic to be announced)
Gaitee Hussein (ESO)
01/04/19 (Monday)
15:30, MPA Large Seminar Room E.0.11 (MPA, Garching) | ESO Garching
MPA Institute Seminar
Talk — Neutron star merger modelling in the era of multimessenger astronomy
Ricard Ardevol (MPA)
11:00, MPE Seminar Room 1.1.18b | ESO Garching
MPE Talk
Talk — Galaxy assembly, outflows and the evolution of disks with IllustrisTNG
Annalisa Pillepich (MPIA Heidelberg)

March 2019

29/03/19 (Friday)
14:00, Library (ESO HQ, Garching) | ESO Garching
Stellar Coffee and Planetary Tea
Talk — New Light on Standard Candles: Cepheids as sensitive stellar laboratories and accurate cosmic yardsticks
Richard I. Anderson (ESO)

Abstract

This talk presents the crucial role that type-I Cepheid variable stars play in improving the understanding of how stars and the cosmos evolve. Starting from the recently reported Hubble constant tension that may imply a need for new physics beyond standard cosmology, I will describe ongoing efforts to measure H0 with an accuracy of 1%. Specifically, I will present an ongoing large observing program operating on both hemispheres that has measured more than 19,000 high-precision radial velocities of Cepheids in support of accurate parallaxes and alternative distance estimates based on Baade-Wesselink-type methods. After highlighting the impact of binaries for accurate parallax determination, I will show that stars physically associated with Cepheids contribute a modest photometric bias of less than 0.23% to H0, which may be further reduced in the future. The second part of the talk discusses Cepheids as sensitive stellar laboratories that probe the effects of rotation on stellar evolution in general and in the context of predicting properties of Cepheid populations, such as the period-luminosity-relation. Time permitting, I will present the curious case of Polaris, our nearest Cepheid, whose Gaia-based luminosity estimate and multi-periodic variability seem to defy theory, thus underlining the urgent need for a more detailed astrophysical understanding of our most important standard candles.

14:00, MPA Large Seminar Room E.0.11 (MPA, Garching) | ESO Garching
Bayes Forum
Talk — 2D Deconvolution with Adaptive Kernel
Dirk Nille (MPI für Plasmaphysik)

Abstract

Adaptive Kernel proved to be valuable in the evaluation of 1D profiles of positive additive distributions in inverse problems. This includes modelling photon fluxes as well as heat fluxes from plasma to the surrounding wall in fusion research. This multi-resolution concept is extended to 2D evaluation, aiming at inverse problems arising in the analysis of image data. Approaches for tackling the problem with optimisation routines as well as "classic" Random Walk and Hamiltonian Monte Carlo integration are presented.

28/03/19 (Thursday)
15:15, Auditorium Eridanus (ESO HQE, Garching) | ESO Garching
Munich Joint Astronomy Colloquium
Talk — Solar interior, helioseismology and neutrinos
Aldo Serenelli (CSIC, Barcelona)
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Abstract

For more than 20 years helioseismology, the study of solar oscillations, has provided an exquisite picture of the solar interior structure. However these oscillations, which are standing acoustic waves in the solar interior, have diminishing amplitudes towards the deep interior and render a blurred picture of the solar innermost core, where most nuclear reactions take place and neutrinos are produced. During the last decade, after the discovery of neutrino oscillations, solar neutrino experiments such as SuperKamiokande, SNO and especially Borexino have continued to develop and improve the accuracy and precision of measurements solar neutrino fluxes. Helioseismic and neutrino constraints offer complementary views of solar interiors and open up the best possibilities to date for testing solar (and stellar) evolution theory as well as a laboratory for particle physics.

The talk will first review the current status of (standard) solar modeling in the context of helioseismic constraints, and discuss where problems and uncertainties lie. About the latter, some emphasis will be placed on recent calculations and experiments of radiative opacities that impact solar and stellar modeling. The second part of the talk will present results of solar neutrino experiments, focusing on Borexino's capabilities to perform solar neutrino spectroscopy, and the constraints on solar interior models that can be obtained. The third part of the talk will briefly discuss the relevance of solar model uncertainties for evolution of low mass stars and the uncertainties in determination of stellar properties based on asteroseismic results might be affected. A short final part will include a discussion of the recent claims of detection of gravity modes (g-modes) in solar oscillations.

Video

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14:00, MPA Large Seminar Room E.0.11 (MPA, Garching) | ESO Garching
MPA Seminar
Talk — Probabilistic Linear Solvers - Treating Approximation as Inference
Simon Bartels (MPI Tuebingen)
27/03/19 (Wednesday)
14:00, USM, Scheinerstr. 1, Munich | ESO Garching
USM Colloquium
Talk — 3D Radiation MHD Simulations of Gas and Dust in Protoplanetary Disks
Mario Flock (MPIA Heidelberg)
26/03/19 (Tuesday)
12:00, Library (ESO HQ, Garching) | ESO Garching
Lunch Talk
Talk — Exploring the dimming event of RW Aur A through multi-epoch VLT/X-Shooter spectroscopy
Maria Koutoulaki (Dublin Institute for Advanced Studies)

Abstract

The study of the inner gaseous disc of YSOs is crucial to understand the physical processes ruling disc evolution and its connection with planet formation. In this talk, I will present our results on the inner disc properties of the CTTS RW AurA. The RW Aur system has captured the attention of astronomers for its dimming events. By using X-SHOOTER spectra obtained when the star was in a bright and in a dim state, we compare the NIR CO emission in order to shed light on this mystery. In general, the NIR CO emission traces a warm (T=2000-5000K) and dense (NCO>1e12cm-2) gas as expected in the innermost region of discs. Both states need a cool (T=2600K) and dense (NCO=7e20cm-2) gas to reproduce the observations, with the emitting region located just inside the dust sublimation radius. By comparing the SED (from ~300 to ~1000 nm) and the CO emission of both states, we find that the dimming can be due to absorption by a layer of large grains with optical depth slowly declining from 2.8 to 1.6. The accretion rate remains constant (Macc~2e-8 Mo/yr) if one assumes that the same layer of dust also occults the accretion line emitting region. This excludes accretion bursts as the main cause of RW AurA brightness variability.

25/03/19 (Monday)
15:30, MPA Large Seminar Room E.0.11 (MPA, Garching) | ESO Garching
MPA Institute Seminar
Talk — Lensed galaxies: a unique opportunity to study the kinematics at high redshift
Francesca Rizzo (MPA)
10:45, Library (ESO HQ, Garching) | ESO Garching
KES: Knowledge Exchange Series
Talk — AGN feedback
Chris Harrison (ESO)

Abstract

Supermassive black holes are found inside all massive galaxies. As these black holes grow (through mass accretion) tremendous amounts of energy is released. Current galaxy evolution theory states that this energy must couple to the gas in the host galaxy (and beyond) and consequently heat the gas or driving it away through outflows. Without this so-called “AGN feedback” models cannot reproduce realistic galaxy populations. However, trying to observationally constrain this process has been an on-going challenge for the last two decades. In this KES I will give a simplified overview of the status of the research on AGN feedback, including the different approaches taken by observers and theorists. Most importantly I will try to provide some clarity on what can be considered a very confusing topic to those outside the field!

22/03/19 (Friday)
10:00, MPE Seminar Room 1.1.18b | ESO Garching
HEG Seminar
Talk — The problematic connection between gamma-ray bursts and ultra-high energy cosmic rays
Filip Samuelsson (KTH Stockholm)
21/03/19 (Thursday)
15:15, Auditorium Eridanus (ESO HQE, Garching) | ESO Garching
Munich Joint Astronomy Colloquium
Talk — The conditions and impact of star formation in a multi-phase interstellar medium
Stefanie Walch (University of Cologne)

Abstract

Star formation takes place in the densest and coldest parts of the interstellar medium (ISM), in dark molecular clouds. These are swept up by multiple supernova explosions on scales of several hundred parsec. While condensing out of the warm ISM, the clouds are continuously fed with fresh gas. Thus, the turbulent substructure and magnetic field properties are imprinted during cloud formation. The formation of dense clouds from the multi-phase ISM, the onset of star formation, and the evolution of the molecular clouds under the impact of stellar feedback from newly born massive stars is studied in high-resolution simulations within the SILCC project. In this talk I will give an overview of the physics and chemistry involved in molecular cloud formation and evolution. After the onset of star formation, the latter is governed by stellar feedback from newly born massive stars. The detailed cloud substructure determines the clouds' vulnerability to stellar feedback processes, in particular to ionizing radiation. Moreover, the ionization state of the gas can be highly variable on scales of tens of parsec due to small-scale turbulent motions within the star-forming clouds, which shield and release the ionizing radiation. This leads to a flickering of the young HII regions on the scale of ~10 pc. On scales of several 100 pc and time scales of tens of Mega-years, the combined feedback from star clusters leads to a reduced star formation rate, such that long depletion time scales are observed.

11:00, MPE Seminar Room 1.1.18b | ESO Garching
ORIGINS Cluster Lecture
Talk — Hunting for the Birthplaces of Supermassive Black Holes in Terabytes of Simulation Data
Michael Norman (Univ. of California)
20/03/19 (Wednesday)
14:00, USM, Scheinerstr. 1, Munich | ESO Garching
USM Colloquium
Talk — Accretion and Feedback in the Formation of Massive Stars
Rolf Kuiper (University of Tübingen)
10:45, Library (ESO HQ, Garching) | ESO Garching
Informal Discussion
Talk — How to (not) find proto-brown dwarfs and why do we care
Oscar Morata (currently ESO visitor)

Abstract

Brown dwarfs populate the lower end of the IMF, and bridge the mass space between low-mass stars and planets. Due to their low mass, there is a strong debate about their formation mechanism(s). In order to confirm or discard those, we need to detect, and characterize, the different stages of brown dwarf evolution, which is no easy task. Ww have followed a systematic approach to the subject in our collaboration, from which we can extract some general lessons, and advice. Nonetheless, interesting and puzzling questions and challenges still remain and it is worth to keep them in mind. 

 

19/03/19 (Tuesday)
16:15, MPP, Freimann, Munich | ESO Garching
MPP Kolloquium
Talk — The H.E.S.S. view on the Very High Energy Universe
Mathieu De Naurois (Ecole Polytechnique)
12:00, Library (ESO HQ, Garching) | ESO Garching
Lunch Talk
Talk — Accretion and Feedback in High-Mass Star Formation
Rolf Kuiper (University of Tübingen)

Abstract

In the course of their accretion phase, massive (proto)stars impact their natal environment in a variety of feedback effects such as thermal heating, MHD-driven protostellar jets and outflows, radiation forces, and photoionization / HII regions. Here, I present our most recent simulation results in terms of the relative strength of the feedback components and the size of the reservoir from which the forming stars gain their masses. For the first time, these simulations include all of the feedback effects mentioned above which allows us to shed light on the physical reason for the upper mass limit of present-day stars. Furthermore, we predict the fragmentation of massive circumstellar accretion disks as a viable road to the formation of spectroscopic massive binaries and the recently observed strong accretion bursts in high-mass star forming regions.

To advertise our latest code development, I will also overview the most recent results obtained in a variety of other astrophysical research fields from the formation of embedded Super-Earth planets’ first atmospheres (Cimerman et al. 2017, MNRAS) to the formation of the progenitors of the first supermassive black holes in the early universe (Hirano et al. 2017, Science).

 

11:00, MPE Seminar Room 1.1.18b | ESO Garching
ORIGINS Cluster Visitor Talk
Talk — Exploring the Cosmic Dawn with Supercomputers: Progress and Remaining Challenges
Michael Norman (Univ. of California)
11:00, MPA Old Lecture Hall 401 | ESO Garching
Cosmology Seminar
Talk — The Chirality of Primordial Gravitational Waves
Evan McDonough (Brown University)
10:00, Fornax (ESO HQ, Garching) | ESO Garching
Star and Planet Formation Seminar
Talk — Revealing the Evolution of Comet Nuclei with Ground Photometric Observations
Rosita Kokotanekova (ESO)

Abstract

The complex nature of comets has earned them a spot among the most interesting objects in the Solar System. Comets are believed to still preserve information about the physical conditions in the protoplanetary disc. At the same time they also bear signatures of the epoch of planetary migration ~4 billion years ago, of the time spent in the outer solar system, as well as of their recent activity.

In the past three decades, a great progress in untangling the intricate history of comets has come from the in-situ studies during a series of space missions which culminated with the Rosetta mission between 2014 and 2016. However, with no plans for space missions to further comets in the next couple of decades, we have to rely more on telescope observations to reveal new details about the unanswered questions in cometary science.

In this talk, I will present results from our effort to study Jupiter-family comet nuclei and their source populations in the Centaur region and the Kuiper Belt. This work has demonstrated that ground photometric observations of the rotation and surface properties of comet nuclei can be key for understanding their evolution.

 

18/03/19 (Monday)
15:30, MPA Old Lecture Hall 401 | ESO Garching
MPA Institute Seminar
Talk — Quasar and stellar radiative feedback in high-z, massive galaxies
Tiago Costa (MPA)
12:00, MPE Seminar Room 1.1.18b | ESO Garching
CAS Seminar
Talk — A Unified Model of the Emission, Extinction, and Polarization of Interstellar Dust
Brandon Hensley (Princeton Univ.) (Princeton University)
15/03/19 (Friday)
14:00, Library (ESO HQ, Garching) | ESO Garching
Stellar Coffee and Planetary Tea
Talk — Luminous Blue Variable stars: mass-loss history and dust production
Claudia Agliozzo (ESO)

Abstract

Massive star evolution is ruled by mass-loss. Through their stellar-winds, massive stars inject mechanical energy and radiation into their surroundings, influencing star formation and galaxy evolution. The generally accepted scenario foresees that very massive stars become Blue Supergiants, enter an instability phase during which they rapidly lose their H envelope through severe mass-loss, and form Wolf-Rayet stars. In this scenario, the unstable Luminous Blue Variable stars (LBVs) have a key role. Observations suggest that LBVs undergo short-duration eruptions, during which they release to the ISM a large fraction of their H-envelope with very high mass-loss rates. Among the many open issues, the mechanism that provokes the LBV instability and violent episodes of mass-loss is not clear, but it has been proposed that it is independent of metallicity, increasing the importance of LBVs in the early Universe. The physical conditions in their ejecta during the giant eruptions seem favourable for the formation and growth of dust. For these reasons LBVs are also candidate producers of dust in the early Universe. However, until recently little has been known about LBV nebulae in low metallicity environments. We carried out a pilot study of LBVs in the Magellanic Clouds with ALMA, VISIR and ATCA, focusing particularly on the mass-loss history and the dust content. I will show some results from our multiwavelength study, compare with Galactic objects, and discuss future perspectives offered by ALMA and the latest generations of instrumentation.

14/03/19 (Thursday)
15:15, Auditorium Eridanus (ESO HQE, Garching) | ESO Garching
Munich Joint Astronomy Colloquium
Talk — The Imaging X-ray Polarimetry Explorer (IXPE)
Martin C. Weisskopf (NASA's Marshall Space Flight Center)
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Abstract

It has been over 44 years since the last extra-solar X-ray polarization observation was performed. As part of the NASA’s Small Explorer Program a new, exciting mission, will, for the first time, produce image-resolved polarimetry of astronomical sources. I am the Principal Investigator of this mission which includes a significant collaboration with the Italian Space Agency. I shall review the history of astrophysical X-ray polarimetry, discussing various experimental techniques and emphasizing the successful method of tracking the photoelectron in a low-Z gas developed in Italy that has allowed this experiment to proceed. After a discussion of the Observatory and its components, I shall present examples of the scientific advances that can be made by adding imaging polarimetry to the X-ray astronomer’s arsenal of tools for probing diverse questions such as: Was the black hole at the center of the Milky Way galaxy one million times more active a few hundred years ago? What is the spin the black holes in microquasars? Is there direct evidence for the effects of quantum electrodynamics in the strong magnetic fields in magnetars?

Video

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11:10, Library (ESO HQ, Garching) | ESO Garching
AGN Club
Talk — The molecular gas content of z~2 active galactic nuclei
Chiara Circosta (ESO)
13/03/19 (Wednesday)
14:00, USM, Scheinerstr. 1, Munich | ESO Garching
USM Colloquium
Talk — What Comets Can Tell us About Planetesimal Formation
Juergen Blum (TU Braunschweig)
11:00, MPE Seminar Room 1.1.18b | ESO Garching
MPE Seminar
Talk — The last major feeding, star formation and feedback episode of Sgr A*
Sergei Nayakshin (Univ. of Leicester)
10:45, Library (ESO HQ, Garching) | ESO Garching
Informal Discussion
Talk — Polarization of light and polarimetry with FORS2
Ana Mourão (CENTRA, IST, ULisboa)

Abstract

Magnitude, color, spectrum, and coordinates of light sources are the main parameters measured in most of the astronomical observations. However, the incoming light might show some degree of polarization. Polarimetric measurements allow to unveil important properties of the source and of the light path, otherwise hidden in common observations. We will discuss some aspects of polarization of light and its measurement with the Focal Reducer/low dispersion Spectrograph, FORS2, mounted on the VLT. In 2019 ESO is celebrating the 20th Anniversary of first light for FORS2.

12/03/19 (Tuesday)
14:00, Auditorium Telescopium (ESO HQE, Garching) | ESO Garching
Star and Planet Formation Seminar
Talk — ALMA challenges to planet accretion theories
Sergei Nayakshin (University of Leicester)

Abstract

High resolution ALMA observations recently provided strong hints for the presence of giant planets in the annular structures in young protoplanetary discs with separations up to 100 AU. I point out that these observations set unique "live" constraints on the process of gas accretion onto sub-Jovian planets that were not previously available. Using a population synthesis approach we compare the properties of the synthetic planets with the ALMA data at the same age. Applying the widely used gas accretion formulae leads to a deficit of sub-Jovian planets and an over-abundance of a few Jupiter mass planets compared to observations. We find that gas accretion onto planets needs to be suppressed by about an order of magnitude to match the observed planet mass function. This slower gas giant growth predicts that the planet mass should correlate with the age of the protoplanetary disc, albeit with a large scatter. This effect is not clearly present in the ALMA data. I show that the suspected ALMA planets are far more likely to form via gravitational fragmentation of massive protoplanetary discs followed by a partial mass loss. Detailed 3D simulations exemplifying this mode of planet formation will be presented.

12:00, Library (ESO HQ, Garching) | ESO Garching
Lunch Talk
Talk — Mass-loss from evolved stars: recent advances and future prospects from surveys to statistics
Peter Scicluna (ASIAA)

Abstract

Outflows of evolved stars drive the chemical evolution of galaxies in the local Universe. Population models dictate that low- to intermediate-mass asymptotic giant branch (AGB) stars dominate this process today, while in the early universe, massive stars and supernovae were likely the main contributors. However, many key issues regarding AGB mass loss remain unresolved. Thanks to Spitzer, a number of Local Group galaxies have been observed in detail, revealing the dust-production rates of all evolved stars, and hence the total dust injection rate for the galaxies. However, measuring the gas mass-loss rates outside our galaxy is prohibitive, making it unlikely that a large sample will be available in the foreseeable future, and systematic studies in the Milky Way remain conspicuously absent. The Nearby Evolved Stars Survey (NESS) aims to fill this gap, by targeting a volume-limited sample of roughly 400 sources within 2 kpc, enabling robust statistical studies of local evolved stars. We will derive the dust and gas return rates in the Solar Neighbourhood, and constrain the physics underlying these processes. I will present a detailed description of the project, including the motivation and strategy, and highlight some of our early results. I will also briefly introduce the tools we are developing that will, along with a catalogue containing all raw and reduced NESS data and a compilation of literature data, be released to the community to aid reproducibility.

09:15, ESO Supernova | ESO Garching
FORS 20th Anniversary
11/03/19 (Monday)
15:30, MPA Old Lecture Hall 401 | ESO Garching
MPA Institute Seminar
Talk — Unveiling the sources of Reionization using the Lyman-alpha transition: a numerical approach
Enrico Garaldi (MPA)
14:00, MPE Seminar Room 1.1.18b | ESO Garching
MPE Seminar
Talk — Hunting for gamma-ray pulsars with multi-wavelength observations
Kwan Lok Li (UNIST)
12:00, MPE Seminar Room 1.1.18b | ESO Garching
CAS Seminar
Talk — The role of Interstellar dust on the formation of Complex Organic Molecules
Ankan Das (ICSP, Kolkata, India)
10:45, Library (ESO HQ, Garching) | ESO Garching
KES: Knowledge Exchange Series
Talk — Gaia's impact and potential for pulsating stars and the distance scale
Richard I. Anderson (ESO)

Abstract

The ESA cornerstone mission Gaia has been relentlessly scanning the full sky for nearly 5 years in order to create an unprecedented three-dimensional map of the Milky Way based on astrometric, photometric, and spectroscopic observations of more than 1.7 billion stars. The two first Gaia data releases (DR1, DR2) have already significantly impacted many areas of astronomy and astrophysics. Yet, the best is still to come with Gaia's mission lifetime having been extended to 6.5 years, and further extensions being likely. However, 10 months after DR2, several issues related to Gaia data have surfaced and are worth discussing.

This KES lecture aims to provide a digestible teaser of Gaia's enormous potential for stellar astrophysics and cosmology while addressing some lessons learned since DR2. To this end, the lecture is split into three main parts: i) a brief overview of the Gaia mission as the largest-ever homogeneous all-sky multi-instrument time-domain survey, ii) Gaia's variability processing with a focus on classical Cepheids and other pulsating stars, and iii) Gaia's impact on the distance scale and its relevance for resolving the Hubble tension. 

07/03/19 (Thursday)
15:15, Auditorium Eridanus (ESO HQE, Garching) | ESO Garching
Munich Joint Astronomy Colloquium
Talk — Extragalactic Planetary Nebulae: kinematic tracers in and around galaxies
Magda Arnaboldi (ESO)

Abstract

Extragalactic Planetary Nebulae (Pne) were mostly studied as secondary distance indicators in late and early-type galaxies, because of the cut-off of their luminosity function at bright magnitudes. With the use of 8 meter and custom built instruments of 4 meter telescopes, they become excellent spatial and kinematic tracers of their parent stellar populations.  In this talk, I will begin with the latest results on the kinematics within galaxies and give examples for the maximal  disk in NGC 628 and multiple disk components in M31. I will then move to the results from the extended Planetary Nebulae Spectrograph (e.PN.S) survey of a sample of local elliptical galaxies (ETGs). While ETGs are either fast and slow rotators at 1 R_e, their stellar halos traced by Pne show an increased  kinematical diversity. By using extended velocity fields out to 5.6 R_e on average, evidence is found for a kinematic transition between inner regions and halos, which depends on the stellar mass and correlates with the spatial transition from the ``in-situ'' to the ``ex-situ'' components  from cosmological simulations of galaxy formation.  I will then present the results based on the kinematics of the halos using Pne for the high mass end of the galaxy population: the cD galaxies in groups and clusters. I will describe how their stellar halos fade into the intra-group/intracluster light and the current measurements of their orbital anisotropy at 50-100 kpc. I will conclude with the constraints on the satellite progenitors of the stars in the outermost regions of these halos/ICL and with a forward look for the use of the ELT.

06/03/19 (Wednesday)
10:45, Library (ESO HQ, Garching) | ESO Garching
Informal Discussion
Talk — High mass white dwarfs as progenitors for double-detonation supernovae Ia
Thomas Kupfer (University of California at Santa Barbara)

Abstract

A recently proposed SN Ia channel is via the so-called sub-Chandrasekhar double-detonation scenario. In this scenario a white dwarf (WD) is orbited by a core Helium(He)-burning compact hot subdwarf star (sdB/sdO) in an ultra-compact orbit (Porb < 80 min). Due to the emission of gravitational waves, the binary is predicted to shrink until the hot subdwarf star fills its Roche lobe and starts mass transfer. He-rich material is then transferred to the C/O-WD companion which will lead to the accumulation of a He-layer on top of the WD. After accreting a small amount He-burning is predicted to be ignited in this shell. This in turn triggers the ignition of carbon in the core even if the WD-mass is significantly lower than the Chandrasekhar limit. However, the number of known systems is still limited. The Zwicky Transient Facility (ZTF) is a new time-domain survey with a 47 sqd. survey camera. I am scientific lead of a high-cadence survey in the Galactic Plane covering the full inner Plane visible from the northern hemisphere as part of ZTF. The goal of this survey is to uncover the population of short period variable stars in the Galaxy. In this talk I will present the discovery of several ultracompact white dwarf binaries with hot subdwarf companions as well as our strategy to find more systems using ZTF.

05/03/19 (Tuesday)
10:00, Fornax (ESO HQ, Garching) | ESO Garching
Star and Planet Formation Seminar
Talk — Circumstellar Dust Distribution in Systems with Two Planets in Resonance
Giovanni Picogna (USM)

Abstract

We investigate via numerical modeling the effects of two planets locked in resonance, and migrating outward, on the dust distribution of the natal circumstellar disk. We test whether the dust distribution exhibits peculiar features arising from the interplay among the gravitational perturbations of the planets in resonance, the evolution of the gas, and its influence on the dust grain dynamics. Models show that a common gap also forms in the dust component similarly to what a single, more massive planet would generate and that outward migration leads to a progressive widening of the dust gap and to a decoupling from the gas gap. As the system evolves, a significantly wider gap is observed in the dust distribution, which ceases to overlap with the gas gap in the inner disk regions.

01/03/19 (Friday)
14:00, Library (ESO HQ, Garching) | ESO Garching
Stellar Coffee and Planetary Tea
Talk — Tomography of evolved star atmospheres
Kateryna Kravchenko (ESO)

Abstract

Cool giant and supergiant stars are among the largest and most luminous stars in the Universe and, therefore, dominate the integrated light of their host galaxies. These stars were extensively studied during last few decades, however their relevant properties like photometric variability and mass loss are still poorly constrained. Understanding of these properties is crucial in the context of a broad range of astrophysical questions including chemical enrichment of the Universe, supernova progenitors, and the extragalactic distance scale.

Atmospheres of giant and supergiant stars are characterized by complex dynamics due to different interacting processes, such as convection, pulsation, formation of molecules and dust, and the development of mass loss. Dynamical processes in stellar atmospheres impact the formation of spectral lines producing their asymmetries and Doppler shifts. Thus, by studying the line-prole variations on spatial and temporal scales it is possible to reconstruct atmospheric motions in evolved stars. As will be shown in this thesis, a tomographic method is an ideal technique for this purpose. It is applied to pulsating Mira-type stars and RSG stars in order to better characterize their atmospheres and better understand respective mechanisms responsible for their photometric variability and mass loss.

February 2019

28/02/19 (Thursday)
12:00, MPE Seminar Room 1.1.18b | ESO Garching
CAS Seminar
Talk — Inflows and Outflows from Low Mass Protostars
Diego Mardones (MPE)
27/02/19 (Wednesday)
14:00, USM, Scheinerstr. 1, Munich | ESO Garching
USM Colloquium
Talk — Interstellar Chemistry of Simple Molecules in Gas and Ice
Miwa Goto (LMU)
26/02/19 (Tuesday)
16:15, MPP, Freimann, Munich | ESO Garching
MPP Kolloquium
Talk — AI at the LHC
Markus Stoye (Imperial College London)
12:00, Library (ESO HQ, Garching) | ESO Garching
Lunch Talk
Talk — Stellar chemo-kinematics of isolated dwarf galaxies
Salvatore Taibi (Instituto de Astrofísica de Canarias)

Abstract

The study of dwarf spheroidal galaxies (dSph) is of great importance to understand galaxy evolution at the low-mass end. In the Local Group (LG) the majority of them are found to be satellites of the Milky Way or M31. Although the closest ones have been studied in great detail, it is hard to constrain if their present-day observed properties are mainly caused by internal or environmental mechanisms.

To minimize environmental effects and gain an insight into their intrinsic properties, we are studying two isolated dSph galaxies in the LG, i.e. Cetus and Tucana, located far beyond the virial radius of the Milky Way and M31. These isolated dSphs, are also interesting because they break the morphology-density relation in the LG.

In this talk I will present results from a sizable spectroscopic sample of individual red giant branch stars taken with the VLT/FORS2 instrument in Cetus and Tucana dSphs. The spectra cover the near-IR CaII triplet wavelength region, from which we have obtained line-of-sight velocities and metallicities ([Fe/H]). The wide-area coverage of our data allowed us to obtain information on the large-scale kinematical and chemical properties of the considered galaxies, such as the possible presence of rotation, metallicity gradients, and multiple chemo-kinematic components. Results on the Cetus and Tucana dSphs place more stringent constraints on the formation mechanisms that led to their present-day morphology.

11:00, MPA Large Seminar Room E.0.11 (MPA, Garching) | ESO Garching
Cosmology Seminar
Talk — Probing cosmology with Dark Matter Halo Sparsity from Galaxy Cluster Observations
Pier Stefano Corasaniti (LUTH, Obs. of Paris)
25/02/19 (Monday)
15:30, MPA Large Seminar Room E.0.11 (MPA, Garching) | ESO Garching
MPA Institute Seminar
Talk — Quasar and stellar radiative feedback in high-z, massive galaxies
Tiago Costa (MPA)
10:45, Library (ESO HQ, Garching) | ESO Garching
KES: Knowledge Exchange Series
Talk — The Tully-Fisher Relation
Federico Lelli (ESO)

Abstract

The Tully-Fisher (TF) relation is one of the tightest scaling laws in extra-galactic Astronomy, linking the visible mass of a galaxy to its outer rotation velocity. I will start with a brief historical overview of the TF relation and its application as a distance indicator. I will then focus on the physics behind the TF relation and its implications for dark matter and cosmology. In particular, the small scatter of the TF relation and the lack of residual correlations with galaxy radius lead to a number of non-trivial fine-tuning problems for current models of galaxy formation.

21/02/19 (Thursday)
15:15, Auditorium Eridanus (ESO HQE, Garching) | ESO Garching
Munich Joint Astronomy Colloquium
Talk — Why Circumgalactic Matter Matters for Galaxy Evolution
Jessica K. Werk (University of Washington)
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Abstract

The circumgalactic medium (CGM; non-ISM gas within a galaxy virial radius) regulates the gas flows that shape the evolutionary paths of galaxies. It likely contains most of the metals lost in galaxy winds and enough material to sustain star-formation for billions of years.  Owing to the vastly improved capabilities in space-based UV spectroscopy with the installation of HST/COS, observations and simulations of the CGM have emerged as the new frontier of galaxy evolution studies. In this talk, I will describe observational constraints we have placed on the origin and fate of this material by studying the gas kinematics, metallicity and ionization state of gas 10 - 200 kpc from galaxies’ stars. I will conclude by introducing several exciting new techniques for resolving the gaseous structures in the CGM, and by posing unanswered questions about the CGM that will be addressed with future survey data and hydrodynamic simulations in a cosmological context.

Video

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20/02/19 (Wednesday)
14:00, USM, Scheinerstr. 1, Munich | ESO Garching
USM Colloquium
Talk — Shaping evolved star winds: new views with ALMA
Liz Humphreys (ESO)
10:45, Library (ESO HQ, Garching) | ESO Garching
Informal Discussion
Talk — Metals as tracers of galaxy evolution
Francesco Belfiore (ESO)

Abstract

The evolution of galaxies is largely shaped by the interplay between inflows, star formation and feedback processes. Heavy elements are key tracers of this cycle of baryons in and out of galaxies. In this talk I will use observations of nearby galaxies to explore the link between metal enrichment and their history of star formation. While this approach is typically employed in systems where individual stars can be resolved, I will discuss the challenges involved in measuring gas and stellar metallicities from integrated light. I will then explore what can be learnt from applying chemical evolution models to the overall galaxy population, as observed in large spectroscopic surveys.

19/02/19 (Tuesday)
16:15, MPP, Freimann, Munich | ESO Garching
MPP Kolloquium
Talk — Neutrino Fingerprints of the High Energy Sky
Irene Tamborra (Niels Bohr Institute)
12:00, Library (ESO HQ, Garching) | ESO Garching
Lunch Talk
Talk — Towards a new paradigm of dust structure in AGN: Dissecting the mid-IR emission of Circinus galaxy
Marko Stalevski (Astronomical Observatory of Belgrade)

Abstract

Recent observations which resolved the mid-infrared (MIR) emission of nearby active galactic nuclei (AGN), revealed that their dust emission appears prominently extended in the polar direction, at odds with the expectations from the canonical dusty torus. This polar dust, tentatively associated with dusty winds driven by radiation pressure, is found to have a major contribution to the MIR flux from scales of a few to hundreds of parsecs. When facing a potential change of paradigm, case studies of objects with the best intrinsic resolution are essential. One such source with a clear detection of polar dust is a nearby, well-known AGN in the Circinus galaxy. Motivated by observations across a wide wavelength range and on different spatial scales, we proposed a phenomenological model consisting of a thin dusty disk and a large-scale polar outflow in the form of a hyperboloid shell. With detailed radiative transfer modeling, we demonstrated that such a model is able to explain the peculiar MIR morphology on large scales seen by VLT/VISIR and the interferometric data from VLTI/MIDI which probe the small scales. In contrast, while providing a good fit to the integrated MIR spectrum, the dusty torus model fails to reproduce the spatially resolved interferometric data. Our results call for caution when attributing dust emission of unresolved sources entirely to the torus and warrant further investigation of the MIR emission in the polar regions of AGN. We put forth the disc + wind model of Circinus as a prototype for the dust structure in the polar dust AGN population.

10:00, Fornax (ESO HQ, Garching) | ESO Garching
Star and Planet Formation Seminar
Talk — Interpreting the proto-planetary disks dust radii measured by ALMA surveys
Giovanni Rosotti (Leiden Observatory)
18/02/19 (Monday)
15:30, MPA Old Lecture Hall 401 | ESO Garching
MPA Institute Seminar
Talk — Unravelling the formation history of the Milky Way with Galactic surveys and cosmological hydrodynamical simulations
Robert Grand (MPA)
14/02/19 (Thursday)
15:15, Auditorium Eridanus (ESO HQE, Garching) | ESO Garching
Munich Joint Astronomy Colloquium
Talk — Chemical Characterization of Extrasolar Planets
Nikku Madhusudhan (Institute of Astronomy, University of Cambridge)
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Abstract

Exoplanetary discoveries in the past two decades have unveiled an astonishing diversity in the physical characteristics of exoplanetary systems, including their orbital properties, masses, radii, equilibrium temperatures, and stellar hosts. Exoplanets known today range from gas-giants to nearly Earth-size planets, and some even in the habitable zones of their host stars. Recent advances in exoplanet observations and theoretical methods are now leading to unprecedented constraints on the physicochemical properties of exoplanetary atmospheres, interiors, and their formation conditions.

I will discuss the latest developments and future prospects of this new era of exoplanetary characterization. In particular, I will present some of the latest constraints on atmospheric chemical compositions of exoplanets, made possible by state-of-the-art high-precision observations from space and ground, and their implications for atmospheric processes and formation conditions of exoplanets. The emerging framework for using atmospheric elemental abundance ratios for constraining +the origins and migration pathways of giant exoplanets will be discussed along with their implications for smaller rocky planets. A survey of theoretical and observational directions in the field will be presented along with several open questions on the horizon.

Video

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11:00, MPE Seminar Room 1.1.18b | ESO Garching
MPE Seminar
Talk — X-ray, SZ and dark matter in galaxy clusters
Stefano Ettori (INAF, Bologna)

Abstract

Galaxy clusters are dark-matter dominated systems enclosed in a volume that is a high-density microcosm of the rest of the universe. What is their true mass scale? What are the statistical properties of the represenatative population? How does their detectability depend on baryon physics? We have learnt a lot on these fundamental questions with our current projects, like XMM-Newton Cluster Outskirts Project (X-COP) and CLASH. More has to be understood and will be the focus of our next XMM-Newton Heritage Cluster Project that will pave the way in using the next generation of observatories, like XRISM eROSITA Euclid Athena, to construct a consistent picture of the formation and composition of galaxy clusters.

13/02/19 (Wednesday)
14:00, USM, Scheinerstr. 1, Munich | ESO Garching
USM Colloquium
Talk — Probing the protosolar disk using dust filtering of the gas giants in the early Solar System
Troels Haugbolle (Niels Bohr Inst., Copenhagen)
12:00, MPE room III X2 209 | ESO Garching
CAS Seminar
Talk — Methanol ice in L 1544
Miwa Goto (USM)
11:00, MPE Seminar Room 1.1.18b | ESO Garching
MPE Seminar
Talk — The variable sky through different eyes
Liliana Sandoval Rivera (Texas Tech Univ.)
10:15, Library (ESO HQ, Garching) | ESO Garching
Informal Discussion
Talk — Unconscious bias: what is it, what does it do and what we can do about it
Sara Lucatello (INAF, Padova)

Abstract

The unconscious brain processes are an important part of everyday life, but what effect do they have on our work, on the choices we make in the professions and our interplay with colleagues? I will present a few findings and discuss possible measures to adopt in order to make the workplace a fairer environment.

12/02/19 (Tuesday)
16:15, MPP, Freimann, Munich | ESO Garching
MPP Kolloquium
Talk — Errors on Errors: Refining Statistical Analyses for Particle Physics
Glen Cowan (Royal Holloway, Univ. of London)
15:00, MPA Large Seminar Room E.0.11 (MPA, Garching) | ESO Garching
Gender Forum
Talk — Genderismus. How 'gender' became a populist thing
Paula-Irene Villa (Chair of Sociology and Gender Studies Dept. LMU)
12:00, Library (ESO HQ, Garching) | ESO Garching
Lunch Talk
Talk — From lunar eclipses to exoplanet atmosphere observations
Fei Yan (University of Göttingen)

Abstract

Transit spectroscopy is one of the main techniques for exoplanet atmosphere characterisation. Since a lunar eclipse has a similar geometry as exoplanet transit, it can be used to observe the Earth transiting the Sun. In this talk, I will present three lunar eclipses observations and three topics we learnt from these observations: Earth’s transmission spectrum, Rossiter-McLaughlin effect of the Earth transiting the Sun, stellar line’s center-to-limb variations during lunar eclipse. I will also present how we apply these knowledge to exoplanet atmosphere characterisations, especially the detection of sodium, hydrogen and helium in exoplanet atmospheres.

11:00, MPA Large Seminar Room E.0.11 (MPA, Garching) | ESO Garching
Cosmology Seminar
Talk — Evidence for Cosmic Hemispherical Asymmetry
Tarun Souradeep (IUCAA)
11/02/19 (Monday)
15:30, MPA Large Seminar Room E.0.11 (MPA, Garching) | ESO Garching
MPA Institute Seminar
Talk — Thermal instability and multiphase gas in the circumgalactic medium
Prateek Sharma (currently MPA)
14:00, MPE Seminar Room 1.1.18b | ESO Garching
MPE Talk
Talk — Why are there black holes at the centres of galaxies
Nadine Neumayer (MPIA, Heidelberg)
10:45, Fornax (ESO HQ, Garching) | ESO Garching
KES: Knowledge Exchange Series
Talk — HORIZON: Beyond the Edge of the Visible Universe
Eiichiro Komatsu (MPA)

Abstract

In collaboration with a renowned movie director Hiromitsu Kohsaka, who is specialised on full-dome movies (which you would watch in a full-dome projection of the planetarium), we have created the world’s first full-dome movie on the cosmic microwave background (CMB). In this 45-minutes movie, you will learn the history and physics of the CMB in an intuitive manner, with incredible computer graphics and beautiful original music. Actors and actresses are real people, but most of the other stuff are CGs.

While we cannot show this movie yet in the full-dome of ESO Supernova, I will show this on a flat screen. Enjoy! The trailer is available at: https://www.youtube.com/watch?v=CQbZi4wfoaw

07/02/19 (Thursday)
15:15, Auditorium Eridanus (ESO HQE, Garching) | ESO Garching
Munich Joint Astronomy Colloquium
Talk — The New Era of Stellar Physics
Matteo Cantiello (Flatiron Institute, New York)
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Abstract

Stellar astrophysics is undergoing a renaissance driven by new observational and theoretical capabilities. Wide-field time-domain surveys have uncovered new classes of stellar explosions, helping to understand how stars evolve and end their lives. Gravitational-wave astronomy is providing exciting insights in the properties of the final remnants of massive stars. Asteroseismology, the study of waves in stars, is also producing dramatic breakthroughs in stellar structure and evolution. Thanks to space astrometry, accurate distances are now available for an unprecedented number of galactic stars. From the theoretical standpoint, it is increasingly possible to study aspects of the three-dimensional structure of stars using targeted numerical simulations. These studies can then be used to develop more accurate models of these physics in one-dimensional stellar evolution codes.

I will review some of the most important results in stellar physics of the last few years, and highlight what are the most relevant puzzles that still need to be solved. I will put particular emphasis on the physics of massive stars, which are the progenitors of core-collapse supernovae, gamma-ray bursts and the massive compact remnants observed by LIGO.

Video

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06/02/19 (Wednesday)
14:00, USM, Scheinerstr. 1, Munich | ESO Garching
USM Colloquium
Talk — Shaping an new model for low- and high-mass star-formation
Alvaro Hacar Gonzalez (Leiden Observ.)
12:00, MPE Seminar Room 1.1.18b | ESO Garching
CAS Seminar
Talk — Constraining the infalling envelope of embedded protostars: BHR71 and its hot corinos
Yao-Lun Yang (UT-Austin)
10:45, Library (ESO HQ, Garching) | ESO Garching
Informal Discussion
Talk — Gravitational time delays and the measurement of H_0
Sherry Suyu (MPA)

Abstract

Strong gravitational lenses with measured time delays between the multiple images can be used to determine the Hubble-Lemaître constant (H_0) that sets the expansion rate of the Universe. Measuring H_0 is crucial for inferring properties of dark energy, spatial curvature of the Universe and neutrino physics.  I will describe techniques for measuring H_0 from lensing with a realistic account of systematic uncertainties, and show the latest results from the H0LiCOW program.  I will show the bright prospects of gravitational lens time delays as an independent and competitive cosmological probe.

05/02/19 (Tuesday)
16:15, MPP, Freimann, Munich | ESO Garching
MPP Kolloquium
Talk — A pragmatic approach to formal fundamental physics
Daniel Friedan (Rutgers University)
04/02/19 (Monday)
17:15, HS2, Physik TUM Garching | ESO Garching
Muenchener Physik Kolloquium
Talk — Plasmonics - hot fields and hot electrons
Stefan Maier (LMU)
16:00, MPE Seminar Room 1.1.18b | ESO Garching
MPE Seminar
Talk — The growth of large-scale structure in the Universe, seen through X-ray vision
Aurora Simionescou (SRON)
15:30, MPA Large Seminar Room E.0.11 (MPA, Garching) | ESO Garching
MPA Institute Seminar
Talk — Distance measurements with type II supernovae: II supernovae: from the expanding photosphere method to automated spectral fitting
Christian Vogl (MPA)
11:00, Library (ESO HQ, Garching) | ESO Garching
ESO/MPA/MPE "Gas Matters" Club
Talk — MUSE reveals metal-enriched absorbers in the circum-galactic medium (CGM) of a radio galaxy at z=2.9
Sthabile Kolwa (ESO)

January 2019

31/01/19 (Thursday)
15:15, Auditorium Eridanus (ESO HQE, Garching) | ESO Garching
Munich Joint Astronomy Colloquium
Talk — Stellar Population Models
Claudia Maraston (University of Portsmouth)

Abstract

Stellar population synthesis models describing the energetic emission and stellar mass distribution of galaxies and star clusters are the essential analysis tool in astrophysics and cosmology. They are used to determine the physics of stellar systems (formation ages, star formation history and chemical composition) and dark matter fractions from data, to predict the spectral energy distribution of simulated galaxies, to trace cosmic time for constraining cosmological parameters , to predict the number, mass and location of stellar remnants giving origin to gravitational waves. Given their widespread use and core role, the accuracy of population synthesis models needs to be constantly improved for keeping pace with progress in instrumentation.

In this talk I shall appraise the progress made over the past two decades focusing on the most significant leaps - the treatment of late stages of stellar evolution and the inclusion of detailed chemistry - which starting from Munich have stimulated substantial work around the globe. I shall then introduce the next step in population model calculations, which will leverage the exploitation of current and future data and hopefully provide the solution to some current puzzles, including the universality of the Initial Mass Function.

11:10, Library (ESO HQ, Garching) | ESO Garching
AGN Club
Talk — The First Quasars and their surroundings... A tale from your favorite MUSE
Emanuele P. Farina (MPIA/MPA)
30/01/19 (Wednesday)
14:00, USM, Scheinerstr. 1, Munich | ESO Garching
USM Colloquium
Talk — Giant Planet Formation in the Pebble Accretion Scenario
Bertram Bitsch (MPIA)
12:15, MPE Seminar Room 1.1.18b | ESO Garching
CAS Seminar
Talk — Formation of Interstellar Complex Organic Molecules (COMs): An ab initio Molecular Dynamics Study
Natalia Inostroza (Universidad Autonoma de Chile)
11:00, MPE Seminar Room 1.1.18b | ESO Garching
MPE Seminar
Talk — Astrophysical Imaging with Information Field Theory
Julia Stadler (Durham University)
10:45, Library (ESO HQ, Garching) | ESO Garching
Informal Discussion
Talk — Recent advances in fitting heterogeneous datasets
Peter Scicluna (ASIAA)

Abstract

As astronomy advances, the biggest gains are often found by combining different kinds of data in a single analysis, e.g. combinations of photometry, spectroscopy, imaging etc. However, such combinations pose a number of statistical challenges that inhibit simple analyses and require new tools to solve them. A key challenge is self-consistently combining data with radically different statistical and systematic uncertainties. I will highlight some recent advances in forward-modelling astronomical data that dramatically improve this situation, before presenting a new tool to fit general combinations of observations.

29/01/19 (Tuesday)
16:15, MPP, Freimann, Munich | ESO Garching
MPP Kolloquium
Talk — Probing the neutrino mass with calorimetric electron capture spectroscopy
Andrea Giachero (INFN of Milano-Bicocca)
14:00, MPE Seminar Room 1.1.18b | ESO Garching
High Energy Seminar
Talk — Elemental abundances and chemical enrichment in the hot intracluster medium
Francois Mernier (MTE-ELTE, Budapest)
12:00, Library (ESO HQ, Garching) | ESO Garching
Lunch Talk
Talk — Galactocentric variation of the gas-to-dust ratio and its relation with metallicity
Andrea Giannetti (Istituto di Radioastronomia, Bologna)

Abstract

The assumption of a gas-to-dust mass ratio is a common approach to estimate the basic properties of molecular clouds, from (sub)mm continuum observations of the dust. In the Milky Way a single value is used at all galactocentric radii, independently of the observed metallicity gradients. Both models and extragalactic observations suggest that this quantity increases for decreasing metallicity Z, typical of the outer regions in disks, where fewer heavy elements are available to form dust grains. We investigate the variation of the gas-to-dust ratio as a function of galactocentric radius and metallicity, to allow a more accurate characterisation of the quantity of molecular gas across the galactic disk, as derived from observations of the dust.

Observations of the optically thin C18O (2-1) transition were obtained with the APEX telescope for a sample of 23 bright star-forming regions in the far outer Galaxy (Rgc>14 kpc). From the modelling of this line and of the spectral energy distribution of the selected clumps we compute the gas-to-dust ratio and compare it to that of well-studied sources from the ATLASGAL TOP100 sample in the inner galactic disk. The gas-to-dust ratio is found to increase with galactocentric radius, whereas the dust metallicity decreases, the most common situation also for external late-type galaxies, suggesting that grain growth dominates over destruction. The predicted gas-to-dust ratio is in excellent agreement with the estimates in Magellanic clouds, for the appropriate value of Z.

11:00, MPE room III X2 209 | ESO Garching
MPE Seminar
Talk — The environmental effect on galaxy evolution at z=2: high CO excitation, galaxy interactions, and the sub-M* population
Rosemary Coogan (Univ. of Sussex)
11:00, MPA Large Seminar Room E.0.11 (MPA, Garching) | ESO Garching
Cosmology Seminar
Talk — Radiative transfer through gas and dust
Martin Glatzle (MPA)
28/01/19 (Monday)
17:15, LMU H030, Schellingstr. 4, Munich | ESO Garching
Muenchener Physik Kolloquium
Talk — Magnetic tweezers to study gene machines at the single-molecule level
David Dulin (FAU, Erlangen-Nuernberg)
15:30, MPA Large Seminar Room E.0.11 (MPA, Garching) | ESO Garching
MPA Institute Seminar
Talk — The oxygen abundance of nearby galaxies from IFU data
Igor Zinchenko (currently at MPA)
14:00, MPE Seminar Room 1.1.18b | ESO Garching
CAS Seminar
Talk — Gas phase Elemental abundances in Molecular cloudS (GEMS)
Asuncion Fuente (OAN, Madrid)
24/01/19 (Thursday)
15:15, Auditorium Eridanus (ESO HQE, Garching) | ESO Garching
Munich Joint Astronomy Colloquium
Talk — Cosmic and other Bell Tests
Anton Zeilinger (Institute for Quantum Optics and Quantum Information Austrian Academy of Sciences and University of Vienna)

Abstract

In experiments on Bell’s theorem the possibility is tested whether local realistic explanations of the correlations between entangled particles can explain the observed correlations. In the talk, I will first discuss possible loopholes in tests of Bell‘s Inequalities. I will then focus on the so-called freedom of choice loophole. This loophole is related to the demand that the measurements of correlations on two (or in principle more) entangled particles are free and independent. I will then in detail report on tests of Bell’s Inequality where cosmic sources are used to provide independent random input for the measurements t entangled photons. In the first experiment, stars within our Milky Way were used and in the second one, distant quasars. Another experiment has used choices of random numbers by humans. These numbers were directed to 13 experiments located globally at 12 different places. Finally, I will briefly mention the implementation of quantum cryptography between Europe and China using the Chinese quantum satellite Micius.

23/01/19 (Wednesday)
11:00, MPE Old Seminar Room 209 | ESO Garching
High Energy Seminar
Talk — Simulation of eROSITA Observations of Supernova Remnant Candidates
Gerson Rodrigues (HEG, MPE)
10:45, Library (ESO HQ, Garching) | ESO Garching
Informal Discussion
Talk — ELT Instrumentation Q&A
Joël Vernet, Ralf Siebenmorgen, Vincenzo Mainieri, Suzanne Ramsay (ESO)

Abstract

As a sequel to the Q&A session on the ELT telescope, the Project Scientists of the ELT instruments will provide an opportunity to ask question on those facilities.

A short introduction to METIS, HARMONI, MICADO+MAORY, MOSAIC and HIRES instruments will be given. Thereafter, the floor will be open for questions.

22/01/19 (Tuesday)
16:15, MPP, Freimann, Munich | ESO Garching
MPP Kolloquium
Talk — Asymptotic symmetries of gravity
Marc Henneaux (Univ. of Brussels)
12:00, Library (ESO HQ, Garching) | ESO Garching
Lunch Talk
Talk — Accurate imaging in radio interferometry: Optimal gridding and degridding
Haoyang Ye (University of Cambridge)

Abstract

The discussion on the choice and performance of different gridding functions can be dated back to 1960s by Liz Waldram in Radio Astronomy group at Cavendish. In radio interferometry imaging process, the Fourier transform relation between the visibility data and the sky brightness distribution is usually implemented by Fast Fourier Transform (FFT), where a procedure called ‘gridding’ of convolving visibilities with a chosen gridding function is needed to assign visibility values into uniformly sampled grids. The spheroidal function has been widely used to suppress aliasing effects since early 1980s. We proposed "Least-misfit gridding function" under the criteria of minimising the difference between the DFT and FFT results. It is proved to have a better aliasing suppression performance than the spheroidal function on simulated dataset. It also minimises the DFT and FFT difference, outperforming the spheroidal function at least 10^2 times with the same gridding width and image cropping ratio. The least--misfit gridding function with a support width of 7 and an image cropping rate of 0.5 is recommended to be applied both into gridding and degridding process, so as to achieve the single precision in terms of the image misfit and visibility misfit respectively. Its application on our newly proposed wide-field imaging method can achieve the single and double precision with the gridding width equals to 7 and 14 respectively.

11:00, MPA Large Seminar Room E.0.11 (MPA, Garching) | ESO Garching
Cosmology Seminar
Talk — How galaxies form stars: the connection between local and global star formation in galaxies
Vadim Semenov (Univ. Chicago)
10:00, Fornax (ESO HQ, Garching) | ESO Garching
Star and Planet Formation Seminar
Talk — Sub-arcsecond Resolution Observations of Class 0/I Protostars
Dominique Segura-Cox (MPE)

Abstract

Circumstellar disks are fundamental for accretion and angular momentum distribution during the early phases of star formation. Class 0 objects are the youngest protostars and most embedded in their natal envelopes, and circumstellar disks can form even at this earliest stage of star formation, yet the envelopes enshrouding Class 0 and Class I protostars have made detection of young protostellar disks difficult.  Our high-resolution work with the VLA and ALMA  towards some of the youngest protostars addresses a variety of questions regarding the frequency, dust properties, kinematics, and chemistry at the earliest times. 

21/01/19 (Monday)
17:15, HS2, Physik TUM Garching | ESO Garching
Muenchener Physik Kolloquium
Talk — Electronic structure and electron dynamics in two-dimensional materials
Philip Hofmann (Aarhus Univ.)
15:30, MPA Large Seminar Room E.0.11 (MPA, Garching) | ESO Garching
MPA Institute Seminar
Talk — Joint image-visibility studies of the Sunyaev-Zeldovich effect
Luca di Mascolo (MPA)
11:00, Library (ESO HQ, Garching) | ESO Garching
ESO/MPA/MPE "Gas Matters" Club
Talk — What can we learn about the interstellar medium of nearby (and high-z) galaxies using far-infrared lines?
Rodrigo Herrera-Camus (MPE)
17/01/19 (Thursday)
15:15, Auditorium Eridanus (ESO HQE, Garching) | ESO Garching
Munich Joint Astronomy Colloquium
Talk — Forming Realistic Galaxies: Successes and Challenges
Alyson Brooks (Rutgers, the State University of New Jersey)

Abstract

Just a decade ago it was believed that one could not form realistic dwarf or disk galaxies in cosmological simulations.  The past decade has seen immense progress, through both advances in resolution and development of physically motivated feedback models. Different simulators are generally now capable of forming realistic galaxies that match a wide variety of observed galaxy scaling relations, despite variations in adopted star formation and feedback recipes.

I will discuss the reasons for these successes, but also highlight a couple of areas where simulators are still facing challenges, e.g., in reproducing realistic galaxy bulges.  I will also show that the assumptions simulators have adopted in the classical dwarf regime will lead to widely varying predictions for the properties of ultra-faint dwarf galaxies. Finally, I will highlight future observations that have the potential to tightly constrain the physical conditions required for star formation at the earliest times.

12:00, MPE Seminar Room 1.1.18b | ESO Garching
CAS Seminar
Talk — New simulations and observations of highly- complex molecules in star-forming regions
Robin Garrod (Univ. of Virginia)
11:10, Library (ESO HQ, Garching) | ESO Garching
AGN Club
Talk — Identification of AGN behind the Small Magellanic Cloud through the XMM-Newton survey
Chandreyee Maitra (MPE)
11:00, MPA Large Seminar Room E.0.11 (MPA, Garching) | ESO Garching
Special MPA Colloquium
Talk — From Birth to Chirp - Astrophysics of Gravitational Wave progenitors
Selma de Mink (Univ. of Amsterdam)
16/01/19 (Wednesday)
14:00, USM, Scheinerstr. 1, Munich | ESO Garching
USM Colloquium
Talk — Probing Cosmology with the Dynamics of Voids
Nico Hamaus (LMU)
11:30, MPA Large Seminar Room E.0.11 (MPA, Garching) | ESO Garching
Special MPA Seminar
Talk — Thermal and non-thermal processes in star clusters: observational clues and numerical modeling
Siddharta Gupta (RRI, Bangalore)
11:00, MPA Large Seminar Room E.0.11 (MPA, Garching) | ESO Garching
Special MPA Seminar
Talk — Simulating supermassive black hole formation and evolution
Melanie Habouzit (Flatiron Inst.)
10:45, Library (ESO HQ, Garching) | ESO Garching
Informal Discussion
Talk — Internal Kinematics of Globular Clusters with HST Proper Motions
Laura Watkins (ESO)

Abstract

Proper motions are crucial to fully understand the internal dynamics of globular clusters. To that end, the High-Resolution Space Telescope Proper Motion (HSTPROMO) collaboration has constructed large, high-quality proper-motion catalogues for 22 GCs in the Milky Way. For most clusters, these catalogues provide the most detailed kinematical data to date, with tremendous potential for improving our understanding of the dynamics and structure of individual clusters. Moreover, the size and diversity of the cluster sample, spanning a broad range of cluster properties (including environment and dynamical state), allows new studies of the GC populations as a whole. I will discuss some of our exciting recent results including: the first 2D kinematical maps for a large sample of GCs; the first directly-measured radial anisotropy profiles for a large sample of GCs; the first dynamical distance and mass-to-light ratio estimates for a large sample of GCs; and the first dynamically-determined masses for hundreds of blue-straggler stars across a large GC sample.

15/01/19 (Tuesday)
16:15, MPP, Freimann, Munich | ESO Garching
MPP Kolloquium
Talk — Strong gravitational lensing as an observational probe of dark matter
Simona Vegetti (MPA)
11:30, MPA Large Seminar Room E.0.11 (MPA, Garching) | ESO Garching
Special MPA Seminar
Talk — Ab initio hydrodynamical simulations on galactic scales
Chia-Yu Hu (Flatiron Inst.)
11:00, MPA Large Seminar Room E.0.11 (MPA, Garching) | ESO Garching
Special MPA Seminar
Talk — Detecting dark matter substructures using cold stellar streams
Nilanjan Banik (Univ. of Florida)
14/01/19 (Monday)
17:15, LMU H030, Schellingstr. 4, Munich | ESO Garching
Muenchener Physik Kolloquium
Talk — Synthesis of 2-dimensional Materials for Applications in Electronics
Georg S. Duesberg (Uni Bundeswehr Muenchen)
15:30, MPA Large Seminar Room E.0.11 (MPA, Garching) | ESO Garching
MPA Institute Seminar
Talk — The Cosmic Baryon Cycle
Celine Peroux (currently at MPA)
11:30, MPA Large Seminar Room E.0.11 (MPA, Garching) | ESO Garching
Special MPA Seminar
Talk — Accurate small-scale supermassive black hole dynamics in galactic-scale simulations
Antti Rantala (Univ. of Helsinki)
11:00, MPA Large Seminar Room E.0.11 (MPA, Garching) | ESO Garching
Special MPA Seminar
Talk — Interaction of matter and high energy radiation: from compact objects to intergalactic medium
Ildar Khabibullin (MPA)
10:45, Library (ESO HQ, Garching) | ESO Garching
KES: Knowledge Exchange Series
Talk — Cosmological hydrodynamical simulations: what they are and how to use them (hands-on with IllustrisTNG)
Dylan Nelson (MPA)

Abstract

I will give a short introduction to galaxy formation simulations, including their overall purpose, motivation, and utility for studying various questions within the context of galaxy formation and evolution. First, I will compare the different types, approaches, and computational methods. I will discuss the common physical ingredients -- which physical processes are typically included in current simulations, 'subgrid' models, and future directions in this front. With reference to Illustris and IllustrisTNG in particular, I will discuss model calibration (tuning), and typical 'caveats' to the use of these types of simulations.

In the second half, we will get practical and discuss the simulation outputs -- what kind of data exists, and how it can be used. I will go quickly through how to use the IllustrisTNG public data release (online), including its documentation, getting started tutorials, and examples for data analysis. We can discuss the creation of synthetic (mock) observations, how to compare the simulations to any type of observation that people may have, and other topics of interest.

11/01/19 (Friday)
14:00, MPA Large Seminar Room E.0.11 (MPA, Garching) | ESO Garching
Bayes Forum
Talk — Jaynes's principle and statistical mechanics
Ulrich Schollwoeck (LMU Munich)
10:00, ESO New Cafeteria | ESO Garching
Star and Planet Formation Seminar
Talk — Proxima Centauri b and the detection of exoplanets hidden behind stellar noise
Fabio Del Sordo (Yale University)

Abstract

I will talk about the discovery and confirmation of Proxima b, the current efforts to investigate the presence of other planets orbiting around this star, and the characteristics of Proxima Centauri that act as noise and might hide the imprint of a further planets. I will also outline some of the current ideas to disentangle planetary signal from stellar noise for M Dwarfs and Solar-like stars.

10/01/19 (Thursday)
15:15, Auditorium Eridanus (ESO HQE, Garching) | ESO Garching
Munich Joint Astronomy Colloquium
Talk — Raining on Galaxies and Black Holes: Unifying the Micro and Macro Properties of AGN Feeding and Feedback
Massimo Gaspari (Princeton University)

Abstract

Feeding and feedback tied to supermassive black holes (SMBHs) play central role in the cosmic evolution of galaxies, groups, and clusters of galaxies. The self-regulated active galactic nucleus (AGN) cycle is matter of intense debate. I review key results of our numerical campaign to unveil how SMBHs are tightly coupled to the multiphase gaseous halos, linking the inner gravitational radius to the large Mpc scale and vice versa. Massively parallel magnetohydrodynamic simulations show the turbulent plasma halo radiatively cools via a top-down multiphase condensation rain of warm filaments and molecular clouds. The multiphase precipitation inherits the hot halo kinematics and thermodynamics, ultimately establishing a 'cosmic weather'. In the nuclear region, the recurrent collisions between the clouds and filaments promote angular momentum cancellation and boost the SMBH accretion rate through a mechanism known as Chaotic Cold Accretion (CCA). The CCA rapid variability triggers powerful AGN outflows, which quench the macro cooling flow and star formation, while preserving the atmospheres of galaxies, groups, and clusters in global thermal equilibrium throughout cosmic time. I highlight the key imprints of AGN feedback and feeding, such as bubbles, shocks, turbulence, and condensed structures, with a critical eye toward observational concordance, including the X-ray plasma, optical filaments, and radio molecular clouds.

11:00, Room 313, MPP, Foehringer Ring 6, Munich | ESO Garching
MPP Kolloquium
Talk — On Dark Matter Self Interactions, Viscosity and Cosmic Expansion
Abhishek Atreya (CAPSS, Bose Institute)
09/01/19 (Wednesday)
14:00, Room 313, MPP, Foehringer Ring 6, Munich | ESO Garching
MPP Kolloquium
Talk — CMB constraints on light primordial black holes
Jan Hamann (UNSW Sydney)
08/01/19 (Tuesday)
11:00, MPA Old Lecture Hall 401 | ESO Garching
Cosmology Seminar
Talk — Magnetic fields in spiral galaxies: Results from local and global simulations
Eva Ntormousi (FORTH, Uni Crete)
07/01/19 (Monday)
15:30, MPA Old Lecture Hall 401 | ESO Garching
MPA Institute Seminar
Talk — Gamma-ray bursts from neutron star mergers
Andrei Beloborodov (Columbia Univ.)

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Past Talks

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