Messenger No. 160 (June 2015)

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Telescopes and Instrumentation

2-7 (PDF)
C. Vlahakis et al.
ALMA Extends to 15-kilometre Baselines: Submillimetre Science down to 20-Milliarcsecond Resolution

ADS BibCode:
2015Msngr.160....2V
Section:
Telescopes and Instrumentation
Author(s)/Affiliation(s):
Vlahakis, C.; Testi, L.; Andreani, P.
AA(Joint ALMA Observatory, Santiago, Chile; ESO) AB(ESO) AC(ESO; ESO ALMA Regional Centre)
Abstract:
From September to late November 2014, the Atacama Large Millimeter/submillimeter Array (ALMA) carried out a Long Baseline Campaign to test and verify baselines up to ~15 kilometres for the first time. The tests were successful, demonstrating the power of ALMA to produce submillimetre-wave imaging at resolutions of tens of milliarcseconds. Science Verification observations of five targets, including an asteroid, a protoplanetary disc, an evolved star and a gravitationally lensed high-redshift galaxy, were obtained. The results demonstrate that the scientific leap for which ALMA was planned has been made. A brief overview of the 2014 Long Baseline Campaign and its scientific results are presented.
References:
ALMA Partnership, Brogan, C. L. et al. 2015, ApJL, arXiv:1503.02649 (ALMA III) ALMA Partnership, Fomalont, E. B. et al. 2015, ApJL, arXiv:1504.04877 (ALMA I) ALMA Partnership, Hunter, T. R. et al. 2015, ApJL, arXiv:1503.02650 (ALMA II) ALMA Partnership, Vlahakis, C. et al. 2015, ApJL, arXiv:1503.02652 (ALMA IV) Durech, J. et al. 2011, Icarus, 117, 313; Dye, S. et al. 2015, MNRAS, submitted, arXiv:1503.08720; Fomalont, E. et al. 2014, The Messenger, 155, 19; Kwon, W. et al. 2011, ApJ, 741, 3; Negrello, M. et al. 2010, Science, 440, 1999; Nikolic, B. et al. 2011, The Messenger, 143, 11; Nikolic, B. et al. 2013, A&A, 552, A104; Omont, A. et al. 2013, A&A, 551, A115; Ramstedt, S. et al. 2014, A&A, 570, L14; Rybak, M. et al. 2015a, MNRAS, in press, arXiv:1503.02025; Rybak, M. et al. 2105b, MNRAS, submitted, arXiv:1506.01425; Swinbank, M. et al. 2015, ApJL, in press, arXiV:1505.05148; Tamura, Y. et al. 2015, PASJ, in press, arXiv:1503.07605; van Leeuwen, F. 2007, A&A, 474, 653; Vlemmings, W. H. T. et al. 2015, A&A, 577, 4; Wong, K. C. 2015, ApJL, submitted, arXiv:1503.05558; Zhang, K., Blake, G. A. & Bergin, E. A. 2015, arXiv:1505.00882

Astronomical Science

9-12 (PDF)
M. Maercker et al.
Probing the Effects of Stellar Evolution: The Dust and Gas in Detached Shells around AGB Stars

ADS BibCode:
2015Msngr.160....9M
Section:
Astronomical Science
Author(s)/Affiliation(s):
Maercker, M.; Ramstedt, S.; Leal-Ferreira, M. L.; Olofsson, G.; Floren, H.-G.
AA(Onsala Space Observatory, Dept. of Radio and Space Science, Chalmers University of Technology, Onsala, Sweden) AB(Department of Physics and Astronomy, Uppsala University, Sweden) AC(Argelander Institut für Astronomie, University of Bonn, Germany) AD(Department of Astronomy, Stockholm University, AlbaNova University Center, Sweden) AE(Department of Astronomy, Stockholm University, AlbaNova University Center, Sweden)
Abstract:
In the last stages of their lives, Sun-like stars evolve along the asymptotic giant branch (AGB), and contribute a significant fraction of heavy elements to the interstellar medium, driving the chemical evolution of galaxies and providing the building material for new stars and planets. We observed the detached shells of dust around the evolved carbon AGB star R Scl in polarised, dust-scattered stellar light with the PolCor instrument on the ESO 3.6-metre telescope. The observations show the distribution of the dust in the shell with unprecedented detail. Comparison with high angular resolution observations of the molecular gas with ALMA show that dust and CO emission coincide almost exactly, implying a common evolution of the dust and gas since the creation of the shell. The results give unique insights into thermal pulses — the mechanism responsible for the chemical evolution of the star — and the way evolved stars lose their mass.
References:
González Delgado, D. et al. 2001, A&A, 372, 885; González Delgado, D. et al. 2003, A&A, 399, 1021; Karakas, A. & Lattanzio, J. C. 2007, PASA, 24, 103; Maercker, M. et al. 2010, A&A, 511, A37; Maercker, M. et al. 2012, Nature, 490, 232; Maercker, M. et al. 2014, A&A, 570, A101; Mattsson, L., Höfner, S. & Herwig, F. 2007, A&A, 470, 339; Olofsson, H. et al. 1993, ApJS, 87, 267; Ramstedt, S. et al. 2011, A&A, 531, A148; Schöier, F. L., Lindqvist, M. & Olofsson, H. 2005, A&A, 436, 633
13-17 (PDF)
M. Gullieuszik et al.
OmegaWINGS: A VST Survey of Nearby Galaxy Clusters

ADS BibCode:
2015Msngr.160...13G
Section:
Astronomical Science
Author(s)/Affiliation(s):
Gullieuszik, M.; Poggianti, B.; Fasano, G.; Zaggia, S.; Paccagnella, A.; Moretti, A.; Bettoni, D.; D’Onofrio, M.; Couch, W. J.; Vulcani, B.; Fritz, J.; Omizzolo, A.; Baruffolo, A.; Schipani, P.; Capaccioli, M.; Varela, J.
AA(INAF — Osservatorio astronomico di Padova, Italy) AB(INAF — Osservatorio astronomico di Padova, Italy) AC(INAF — Osservatorio astronomico di Padova, Italy) AD(INAF — Osservatorio astronomico di Padova, Italy) AE(INAF — Osservatorio astronomico di Padova, Italy; Dipartimento di Fisica e Astronomia, Università degli Studi di Padova, Italy) AF(INAF — Osservatorio astronomico di Padova, Italy; Dipartimento di Fisica e Astronomia, Università degli Studi di Padova, Italy) AG(INAF — Osservatorio astronomico di Padova, Italy) AH(Dipartimento di Fisica e Astronomia, Università degli Studi di Padova, Italy) AI(Australian Astronomical Observatory, North Ryde, Australia) AJ(Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, The University of Tokyo, Kashiwa, Japan) AK(Centro de Radioastronomia y Astrofisica, UNAM, Campus Morelia, Mexico) AL(INAF — Osservatorio astronomico di Padova, Italy; Specola Vaticana, Vatican City State) AM(INAF — Osservatorio astronomico di Padova, Italy) AN(INAF — Osservatorio astronomico di Capodimonte, Napoli, Italy) AO(Dipartimento di Fisica, Università Federico II, Napoli, Italy) AP(Centro de Estudios de Fisica del Cosmos de Aragon, Teruel, Spain)
Abstract:
OmegaWINGS is a photometric and spectroscopic survey of 46 nearby galaxy clusters. The photometric part is based on OmegaCAM imaging with the VLT Survey Telescope; the field of view of one square degree covers the whole virial region, extending up to the infall regions of each OmegaWINGS cluster. The ongoing spectroscopic survey will provide about 30 000 spectra with AAOmega on the Australian Astronomical Telescope. OmegaWINGS will provide an extremely detailed and complete view of galaxy populations in clusters. The final data products will include, for each galaxy detected in the target clusters, aperture and surface photometry, morphological type and a reliable characterisation of the stellar populations. The survey will therefore be a unique tool to study the formation and evolution of galaxies in clusters and the interactions of galaxies with the environment.
References:
Calvi, R., Poggianti, B. & Vulcani, B. 2011, MNRAS, 416, 727; D’Onofrio, M. et al. 2014, A&A, 572, A87; Ebeling, H. et al. 2000, MNRAS, 318, 333; Fasano, G. et al. 2006, A&A, 445, 805; Fasano, G. et al. 2015, MNRAS, 449, 3927; Fritz, J. et al. 2014, A&A, 566, A32; Gullieuszik, M. et al. 2015, A&A, accepted, arXiv:1503.02628; Liske, J. et al. 2003, MNRAS, 344, 307; Moretti, A. et al. 2014, A&A, 564, A138; Poggianti, B. M. et al. 2015, ApJS, submitted, arXiv:1504.07105; Vandame, B. 2004, PhD thesis, Université de Nice
18-22 (PDF)
R. J. Smith et al.
The SINFONI Nearby Elliptical Lens Locator Survey (SNELLS)

ADS BibCode:
2015Msngr.160...18S
Section:
Astronomical Science
Author(s)/Affiliation(s):
Smith, R. J.; Lucey, J. R.; Conroy, C.
AA(Centre for Extragalactic Astronomy, Durham University, United Kingdom) AB(Centre for Extragalactic Astronomy, Durham University, United Kingdom) AC(Harvard Smithsonian Centre for Astrophysics, Cambridge, USA)
Abstract:
The SINFONI Nearby Elliptical Lens Locator Survey (SNELLS) is a novel search for strong gravitational lenses among the local early-type galaxy population (redshift zlens < 0.055). Observations of lensing by nearby galaxies can provide especially robust measurements of stellar mass in galaxies, with minimal corrections for dark matter contributions. In turn this leads to constraints on the initial mass function (IMF), i.e., the relative number of stars as a function of their mass at birth. To date, we have discovered two new multiple-image systems, and recovered the one previously known example. Analysing all three systems, we find the mean stellar mass-to-light ratio in these very massive early-type galaxies is consistent with a Milky Way IMF, in contrast to the “heavy” IMFs derived for ellipticals in some recent studies.
References:
Abazajian, K. N. et al. 2009, ApJS, 2009, 182; Bolton, A. S. et al. 2006, ApJ, 638, 703; Campbell, L. et al. 2014, MNRAS, 433, 1231; Cappellari, M. et al. 2013, MNRAS, 432, 1862; Conroy, C. & van Dokkum, P. 2012, ApJ, 760, 71; Kroupa, P. 2001, MNRAS, 322, 231; Schaller, M. et al. 2015, MNRAS, 451, 5765; Sobral, D. et al. 2013, MNRAS, 428, 1128; Smith, R. J. 2014, MNRAS, 443, L69; Smith, R. J. & Lucey, J. R. 2013, MNRAS, 434, 1964; Smith, R. J., Lucey, J. R. & Conroy, C. 2015, MNRAS, 449, 3441; Treu, T. et al. 2010, ApJ, 709, 1195
23-26 (PDF)
T. Zafar et al.
The ESO UVES Advanced Data Products Quasar Sample: Neutral Gas Mass and Metal Abundances in the Universe

ADS BibCode:
2015Msngr.160...23Z
Section:
Astronomical Science
Author(s)/Affiliation(s):
Zafar, T.; Péroux, C.; Vladilo, G.; Centurión, M.; Molaro, P.; D’Odorico, V.; Abbas, K.; Popping, A.; Milliard, B.; Deharveng, J.-M.; Frank, S.
AA(ESO) AB(Aix Marseille Université, CNRS, Laboratoire d’Astrophysique de Marseille (LAM), France) AC(INAF — Osservatorio Astronomico di Trieste, Italy) AD(INAF — Osservatorio Astronomico di Trieste, Italy) AE(INAF — Osservatorio Astronomico di Trieste, Italy) AF(INAF — Osservatorio Astronomico di Trieste, Italy) AG(Center of Excellence in Solid State Physics, University of the Punjab, Lahore, Pakistan) AH(International Centre for Radio Astronomy Research (ICRAR), The University of Western Australia, Crawley, Australia) AI(Aix Marseille Université, CNRS, Laboratoire d’Astrophysique de Marseille (LAM), France) AJ(Aix Marseille Université, CNRS, Laboratoire d’Astrophysique de Marseille (LAM), France) AK(Aix Marseille Université, CNRS, Laboratoire d’Astrophysique de Marseille (LAM), France; Department of Astronomy, Ohio State University, Columbus, USA)
Abstract:
Damped Lyα absorbers (DLAs), seen in the spectra of background quasars, are unique probes to select HI-rich galaxies. We selected a dataset of 250 quasars observed with the Ultraviolet Visual Echelle Spectrograph (UVES) and available through the ESO UVES Advanced Data Products (EUADP) archive, to study the gas and metal properties of 150 damped absorbers. These high-redshift absorbers contain information on the physical state and chemical composition of the interstellar medium and the neutral gas mass, a possible indicator of gas consumption as star formation proceeds. We find no evolution of the neutral gas mass density, with sub-DLAs contributing 8–20% (increasing with redshift). The EUADP dataset provides insights into the nucleosynthetic origin of nitrogen, confirming the bimodal behaviour of [N/α], and also confirms the deficiency of argon in DLAs.
References:
Altay, G. et al. 2011, ApJ, 737, L37; Chiappini, C. et al. 2006, A&A, 449, L27; Cucciati, O. et al. 2012, A&A, 539, A31; Henry, R. B. C., Edmunds, M. G. & Köppen, J. 2000, ApJ, 541, 660; Hopkins, A. M. & Beacom, J. F. 2006, ApJ, 651, 142; Hopkins, A. M., McClure-Griffiths, N. M. & Gaensler, B. M. 2008, ApJ, 682, L13; Izotov, Y. I. & Thuan, T. X. 2004, ApJ, 602, 200; Jenkins, E. B. 2013, ApJ, 764, 25; Kim, T.-S. et al. 2013, A&A, 552, A77 Lagos, C. D. P. et al. 2011, MNRAS, 418, 1649; Lah, P. et al. 2007, MNRAS, 376, 1357; Martin, A. M. et al. 2010, ApJ, 723, 1359; Nava, A. et al. 2006, ApJ, 645, 1076; Péroux, C. et al. 2003, MNRAS, 345, 480; Péroux, C. et al. 2005, MNRAS, 363, 479; Prochaska, J. X., O’Meara, J. M. & Worseck, G. 2010, ApJ, 718, 392; Rao, S. M., Turnshek, D. A. & Nestor, D. B. 2006, ApJ, 636, 610; Spite, M. et al. 2005, A&A, 430, 655; van de Voort, F. et al. 2012, MNRAS, 421, 2809; van Zee, L. et al. 1998, AJ, 116, 2805; Zafar, T. et al. 2011, A&A, 532, A51; Zafar, T., Popping, A. & Péroux, C. 2013a, A&A, 556, A140; Zafar, T. et al. 2013b, A&A, 556, A141; Zafar, T. et al. 2014a, MNRAS, 444, 744; Zafar, T. et al. 2014b, MNRAS, 445, 2093Z

Astronomical News

28-31 (PDF)
M. Rejkuba et al.
Report on the ESO Workshop ''Baryons at Low Densities: The Stellar Halos around Galaxies''

ADS BibCode:
2015Msngr.160...28R
Section:
Astronomical News
Author(s)/Affiliation(s):
Rejkuba, M.; Arnaboldi, M.; Valenti, E.
AA(ESO) AB(ESO) AC(ESO)
Abstract:
The workshop (Stellar Halos 2015) focused on theoretical and observational studies of the faint surface brightness envelopes surrounding luminous galaxies. This field of research has gained much attention in recent years owing to the availability of wide-field cameras, deep and large-area surveys, as well as advances in modelling galaxy formation and evolution. The comparison of the observational properties of stellar halos with the predictions from simulations provides important constraints on the formation of luminous galaxies and their assembly history. An overview of the topics covered at the workshop is presented.
References:
Bullock, J. S. & Johnston, K. V. 2005, ApJ, 635, 931; Eggen, O. J., Lynden-Bell, D. & Sandage, A. R. 1962, ApJ, 136, 748; Longobardi, A. et al. 2015, A&A, in press, arXiv:1504.04369; McConnachie, A. W. et al. 2009, Nature, 461, 66
31-35 (PDF)
C. Vlahakis
Report on the ESO Workshop ''Dissecting Galaxies Near and Far''

ADS BibCode:
2015Msngr.160...31V
Section:
Astronomical News
Author(s)/Affiliation(s):
Vlahakis, C.
AA(Joint ALMA Observatory, Santiago, Chile; ESO)
Abstract:
The workshop explored high-resolution perspectives for the understanding of star formation and the interstellar medium in the era of ALMA. Angular and spectral resolutions are fundamental limitations for our understanding of the properties of galaxies in the nearby and distant Universe. A new generation of instruments and powerful observatories, as well as planned future facilities, is pushing out the boundaries of what was previously possible over the entire electromagnetic spectrum. Held in the approach to ALMA Early Science Cycle 3, the workshop centred on discussing the scientific results and upcoming opportunities afforded by the new capabilities available in the era of ALMA. Some of the science highlights of the meeting are presented.
References:
Alatalo, K. et al. 2013, MNRAS, 432, 1796; ALMA Partnership, Vlahakis, C. et al. 2015, ApJL, in press, arXiv:1504.04877; Davis, T. et al. 2013, MNRAS, 429, 534; Fukui, Y. et al. ApJL, submitted, arXiV:1503.03540; Leroy, A. et al. 2013, ApJ, 146, 19; Meidt, S. et al. 2013, ApJ, 779, 45; Spilker, J. S. et al. 2014, ApJ, 785, 149; Utomo, D. et al. 2015, ApJ, 803, 16
35-37 (PDF)
E. Hatziminaoglou et al.
Report on the ''ALMA/Herschel Archival Workshop''

ADS BibCode:
2015Msngr.160...35H
Section:
Astronomical News
Author(s)/Affiliation(s):
Hatziminaoglou, E.; Zwaan, M.; Testi, L.
AA(ESO) AB(ESO) AC(ESO)
Abstract:
The Herschel mission produced data from 2009 to 2013 and ALMA Cycle 0 began in 2012. The lower frequency Herschel capabilities overlap the higher frequency ALMA bands but, despite differences in spatial resolution, Herschel provides targets for ALMA follow-up. Following up on a previous Herschel ALMA archival workshop, this one provided a large number of comparative studies using both archives. An overview of the workshop is provided, covering topics from cosmology to the Solar System.
References:
Testi, L., Pilbratt, G. & Andreani, P. 2011, The Messenger, 143, 52
37-40 (PDF)
J. Anderson et al.
Fellows at ESO

ADS BibCode:
2015Msngr.160...37.
Section:
Astronomical News
Author(s)/Affiliation(s):
J. Anderson; O. A. Gonzalez; B. Yang
AA(ESO) AB(ESO) AC(ESO)
40-40 (PDF)
ESO
Personnel Movements

ADS BibCode:
2015Msngr.160...40.
Section:
Astronomical News
Author(s)/Affiliation(s):
ESO
AA(ESO)
41-41 (PDF)
ESO
ESO Fellowship Programme 2015/2016

ADS BibCode:
2015Msngr.160...41.
Section:
Astronomical News
Author(s)/Affiliation(s):
ESO
AA(ESO)