Messenger No. 159 (March 2015)

« Back to The Messenger home

Telescopes and Instrumentation

2-5 (PDF)
B. Leibundgut et al.
SPHERE Science Verification

ADS BibCode:
2015Msngr.159....2L
Section:
Telescopes and Instrumentation
Author(s)/Affiliation(s):
Leibundgut, B.; Beuzit, J.-L.; Gibson, N.; Girard, J.; Kasper, M.; Kerber, F.; Lundin, L.; Mawet, D.; McClure, M.; Milli, J.; Petr-Gotzens, M.; Siebenmorgen, R.; van den Ancker, M.; Wahhaj, Z.
AA(ESO) AB(Institut de Planétologie et d’Astrophysique de Grenoble (IPAG), France) AC(ESO) AD(ESO) AE(ESO) AF(ESO) AG(ESO) AH(ESO) AI(ESO) AJ(ESO) AK(ESO) AL(ESO) AM(ESO) AN(ESO)
Abstract:
Science Verification (SV) for the latest instrument to arrive on Paranal, the high-contrast and spectro-polarimetric extreme adaptive optics instrument SPHERE, is described. The process through which the SV proposals were solicited and evaluated is briefly outlined; the resulting observations took place in December 2014 and February 2015. A wide range of targets was observed, ranging from the Solar System, young stars with planets and discs, circumstellar environments of evolved stars to a galaxy nucleus. Some of the first results are previewed.
References:
Beuzit, J.-L. et al. 2006, The Messenger, 125, 29 Hardy, A. et al. 2015, ApJ, 800, L24 Kasper, M. et al. 2012, The Messenger, 149, 17 Yang, B. et al. 2014, CBET, 4035
6-9 (PDF)
H. Boffin et al.
Making FORS2 Fit for Exoplanet Observations (again)

ADS BibCode:
2015Msngr.159....6B
Section:
Telescopes and Instrumentation
Author(s)/Affiliation(s):
Boffin, H.; Blanchard, G.; Gonzalez, O.; Moehler, S.; Sedaghati, E.; Gibson, N.; van den Ancker, M.; Smoker, J.; Anderson, J.; Hummel, C.; Dobrzycka, D.; Smette, A.; Rupprecht, G.
AA(ESO) AB(ESO) AC(ESO) AD(ESO) AE(ESO) AF(ESO) AG(ESO) AH(ESO) AI(ESO) AJ(ESO) AK(ESO) AL(ESO) AM(ESO)
Abstract:
For about three years, it has been known that precision spectrophotometry with FORS2 suffered from systematic errors which made quantitative observations of planetary transits impossible. We identified the longitudinal atmospheric dispersion corrector (LADC) as the most likely culprit, and therefore engaged in a project to exchange the LADC prisms with the uncoated ones from FORS1. This led to a significant improvement in the depth of the FORS2 zero points, a reduction in the systematic noise, and should make FORS2 competitive again for transmission spectroscopy of exoplanets.
References:
Avila, G., Rupprecht, G. & Becker, J. M. 1997, SPIE, 2871, 1135 Bean, J. L. et al. 2011, ApJ, 743, 92 Bean, J. L., Kempton, E. M.-R. & Homeier, D. 2010, Nature, 468, 669 Berta, Z. K. et al. 2011, ApJ, 736, 12 Brown, T. M. 2001, ApJ, 553, 1006
 Burrows, A. S. 2014, Nature, 513, 345 Crossfield, I. J. M. et al. 2013, A&A, 559, A33 Gibson, N. P. et al. 2013a, MNRAS, 428, 3680 Gibson, N. P. et al. 2013b, MNRAS, 436, 2974 Moehler, S. et al. 2010, PASP, 122, 93 Schlawin, E. et al. 2014, ApJ, 783, 5
 Seager, S. & Sasselov, D. D. 2000, ApJ, 537, 916 Sedaghati, E. et al. 2015, A&A, submitted, arXiv:1503.04155 Snellen, I. et al. 2010, Nature, 465, 1049
10-14 (PDF)
S. Moehler et al.
Improving the Quality of FORS2 Reduced Spectra

ADS BibCode:
2015Msngr.159...10M
Section:
Telescopes and Instrumentation
Author(s)/Affiliation(s):
Moehler, S.; Dabo, C. E. G.; Boffin, H.; Rupprecht, G.; Saviane, I.; Freudling, W.
AA(ESO) AB(ESO) AC(ESO) AD(ESO) AE(ESO) AF(ESO)
Abstract:
The FORS2 instrument is one of the most widely used and productive instruments on the Very Large Telescope. This article reports on a project to improve the quality of the reduced FORS2 spectra that can be produced with the software provided by ESO. The result of this effort is that spectra of significantly higher quality can now be produced with substantially lower effort by the science user of the data.
References:
Appenzeller, I. et al. 1998, The Messenger, 94, 1 Bean, J. L., Kempton, E. M.-R. & Homeier, D. 2010, Nature, 468, 669 Boffin, H. M. J. et al. 2012, Science, 338, 773 Freudling, W. et al. 2013, A&A, 559, A96 Halliday, C. et al. 2004, A&A, 427, 397 Hamuy, M. et al. 1994, PASP, 106, 566 Hjorth, J. et al. 2003, Nature, 423, 847 Horne, K. 1986, PASP, 98, 609 Milvang-Jensen, B. et al. 2008, A&A, 482, 419 Mortlock, D. J. et al. 2011, Nature, 474, 616 Oke, J. B. 1990, AJ, 99, 1621 Rupprecht, G. et al. 2010, The Messenger, 140, 2 Sterzik, M. F., Bagnulo, S. & Palle, E. 2012, Nature, 483, 64 Tanvir, N. R. et al. 2009, Nature, 461, 7268
15-18 (PDF)
H. U. Käufl et al.
The Return of the Mid-infrared to the VLT: News from the VISIR Upgrade

ADS BibCode:
2015Msngr.159...15K
Section:
Telescopes and Instrumentation
Author(s)/Affiliation(s):
Käufl, H. U.; Kerber, F.; Asmus, D.; Baksai, P.; Di Lieto, N.; Duhoux, P.; Heikamp, S.; Hummel, C.; Ives, D.; Jakob, G.; Kirchbauer, J.-P.; Mehrgan, L.; Momany, Y.; Pantin, E.; Pozna, E.; Riquelme, M.; Sandrock, S.; Siebenmorgen, R.; Smette, A.; Stegmeier, J.; Taylor, J.; Tristram, K.; Valdes, G.; van den Ancker, M.; Weilenmann, U.; Wolff, B.
AA(ESO) AB(ESO) AC(ESO) AD(ESO) AE(ESO) AF(ESO) AG(Leiden Observatory, the Netherlands) AH(ESO) AI(ESO) AJ(ESO) AK(ESO) AL(ESO) AM(INAF–Osservatorio Astronomico di Padua, Italy) AN(Service d’Astrophysique/DAPNIA/DSM, CEA Saclay, Gif-sur-Yvette, France) AO(ESO) AP(ESO) AQ(ESO) AR(ESO) AS(ESO) AT(ESO) AU(ESO) AV(ESO) AW(Leiden Observatory, the Netherlands) AX(ESO) AY(ESO) AZ(ESO)
Abstract:
The VLT mid-infrared imager and spectrometer VISIR returns to science operations following an extended upgrade period. Among the most important modifications are: the imaging and spectroscopic detectors have been replaced with larger AQUARIUS (1024 by 1024 pixel) detector arrays; the N-band low-resolution grating has been exchanged; and support is now provided for precipitable water vapour monitoring, in order to select the best observing conditions. The AQUARIUS detectors stem from a development for very low background applications which result in excess noise under ground-based conditions. A series of interventions was needed to find a scheme that effectively exploits these detectors for ground-based use, involving the implementation of faster chopping. VISIR has been returned to service at the VLT with enhanced capabilities.
References:
Ives, D. et al. 2014, Proc. SPIE, 9154, 91541J Käufl, H. U. et al. 1991, Experimental Astronomy, 2, 115 Kerber, F. 2012, The Messenger, 148, 9 Kerber, F. et al. 2014a, MNRAS, 439, 247 Kerber, F. et al. 2014b, Proc. SPIE, 9147, 91470C Lagage, P. O. et al. 2004, The Messenger, 117, 12 Lopez, B. et al. 2014, The Messenger, 157, 5 Stapelbroek, M. G. et al. 1984, Proc. IRIS Detector, No. 2
19-22 (PDF)
P. Martinez et al.
The SPEED Project: SPEEDing up Research and Development towards High-contrast Imaging Instruments for the E-ELT

ADS BibCode:
2015Msngr.159...19M
Section:
Telescopes and Instrumentation
Author(s)/Affiliation(s):
Martinez, P.; Preis, O.; Gouvret, C.; Dejongue, J.; Daban, J.-B.; Spang, A.; Martinache, F.; Beaulieu, M.; Janin-Potiron, P.; Abe, L.; Fantei-Cujolle, Y.; Ottogalli, S.; Mattei, D.; Carbillet, M.
AA(Laboratoire Lagrange, UMR7293, Université de Nice Sophia-Antipolis, CNRS, Observatoire de la Côte d’Azur, Nice, France) AB(Laboratoire Lagrange, UMR7293, Université de Nice Sophia-Antipolis, CNRS, Observatoire de la Côte d’Azur, Nice, France) AC(Laboratoire Lagrange, UMR7293, Université de Nice Sophia-Antipolis, CNRS, Observatoire de la Côte d’Azur, Nice, France) AD(Laboratoire Lagrange, UMR7293, Université de Nice Sophia-Antipolis, CNRS, Observatoire de la Côte d’Azur, Nice, France) AE(Laboratoire Lagrange, UMR7293, Université de Nice Sophia-Antipolis, CNRS, Observatoire de la Côte d’Azur, Nice, France) AF(Laboratoire Lagrange, UMR7293, Université de Nice Sophia-Antipolis, CNRS, Observatoire de la Côte d’Azur, Nice, France) AG(Laboratoire Lagrange, UMR7293, Université de Nice Sophia-Antipolis, CNRS, Observatoire de la Côte d’Azur, Nice, France) AH(Laboratoire Lagrange, UMR7293, Université de Nice Sophia-Antipolis, CNRS, Observatoire de la Côte d’Azur, Nice, France) AI(Laboratoire Lagrange, UMR7293, Université de Nice Sophia-Antipolis, CNRS, Observatoire de la Côte d’Azur, Nice, France) AJ(Laboratoire Lagrange, UMR7293, Université de Nice Sophia-Antipolis, CNRS, Observatoire de la Côte d’Azur, Nice, France) AK(Laboratoire Lagrange, UMR7293, Université de Nice Sophia-Antipolis, CNRS, Observatoire de la Côte d’Azur, Nice, France) AL(Laboratoire Lagrange, UMR7293, Université de Nice Sophia-Antipolis, CNRS, Observatoire de la Côte d’Azur, Nice, France) AM(Laboratoire Lagrange, UMR7293, Université de Nice Sophia-Antipolis, CNRS, Observatoire de la Côte d’Azur, Nice, France) AN(Laboratoire Lagrange, UMR7293, Université de Nice Sophia-Antipolis, CNRS, Observatoire de la Côte d’Azur, Nice, France)
Abstract:
An overview is presented of the Segmented Pupil Experiment for Exoplanet Detection (SPEED) testbench. This is an advanced facility in development at the Lagrange Laboratory that will address several of the most critical issues affecting high-contrast imaging for the next generation of optical/near-infrared telescopes. The SPEED testbed can be used to investigate practical solutions for broadband coronography on asymmetric, unfriendly apertures, enabling algorithmic or optical approaches to be developed to minimise segment effects and pupil discontinuity.
References:
Beuzit, J.-L. et al. 2006, The Messenger, 125, 29 Dohlen, K. et al. 2006, Proc. SPIE, 6267, 34D Gonté, F. et al. 2009, The Messenger, 136, 25 Guyon, O. et al. 2014, ApJ, 780, 171 Hénault, F. et al. 2011, Proc. SPIE, 8151, 81510A Kasper, M. et al. 2010, The Messenger, 140, 24 Kasper, M. et al. 2013, High-contrast imaging roadmap for the E-ELT-PCS, ESO internal document Martinez, P. et al. 2014, Proc. SPIE, 9145, 91454E Martinache, F. 2013, PASP, 125, 422 Mas, M. et al. 2012, A&A, 539, 126 Pueyo, L. & Norman, C. 2013, ApJ, 769, 102 Vogt, F. P. A. et al. 2011, PASP, 123, 1434

Astronomical Science

24-29 (PDF)
S. Ertel et al.
An Unbiased Near-infrared Interferometric Survey for Hot Exozodiacal Dust

ADS BibCode:
2015Msngr.159...24E
Section:
Astronomical Science
Author(s)/Affiliation(s):
Ertel, S.; Augereau, J.-C.; Absil, O.; Defrère, D.; Le Bouquin, J.-B.; Marion, L.; Bonsor, A.; Lebreton, J.
AA(ESO; Université Grenoble Alpes, France; CNRS, Institut de Planétologie et d’Astrophysique de Grenoble, France) AB(Université Grenoble Alpes, France; CNRS, Institut de Planétologie et d’Astrophysique de Grenoble, France) AC(Départment d’Astrophysique, Géophysique et Océanographie, Université de Liège, Belgium) AD(Department of Astronomy, Steward Observatory, University of Arizona, USA) AE(Université Grenoble Alpes, France; CNRS, Institut de Planétologie et d’Astrophysique de Grenoble, France) AF(Départment d’Astrophysique, Géophysique et Océannographie, Université de Liège, Belgium) AG(School of Physics, H. H. Wills Physics Laboratory, University of Bristol, United Kingdom) AH(NASA Exoplanet Science Institute, California Institute of Technology, Pasadena, USA; Infrared Processing and Analysis Center, California Institute of Technology, Pasadena, USA)
Abstract:
Exozodiacal dust is warm or hot dust found in the inner regions of planetary systems orbiting main sequence stars, in or around their habitable zones. The dust can be the most luminous component of extrasolar planetary systems, but predominantly emits in the near- to mid-infrared where it is outshone by the host star. Interferometry provides a unique method of separating this dusty emission from the stellar emission. The visitor instrument PIONIER at the Very Large Telescope Interferometer (VLTI) has been used to search for hot exozodiacal dust around a large sample of nearby main sequence stars. The results of this survey are summarised: 9 out of 85 stars show excess exo- zodiacal emission over the stellar photospheric emission.
References:
Absil, O. et al. 2006, A&A, 452, 237 Absil, O. et al. 2013, A&A, 555, 104 Bonsor, A. et al. 2014, MNRAS, 441, 2380 Czechowski, A. & Mann, I. 2010, ApJ, 714, 89 Defrère, D. et al. 2011, A&A, 534, 5 Defrère, D. et al. 2015, ApJ, 799, 1 Ertel, S. et al. 2014, A&A, 570, 128 Le Bouquin, J.-B. et al. 2011, A&A, 535, 67 Lebreton, J. et al. 2013, A&A, 555, 146 Marion, L. et al. 2014, A&A, 570, 127 Mennesson, B. et al. 2014, ApJ, 797, 119 Smith, R. et al. 2009, A&A, 503, 265 Weinberger, A. J. et al. 2015, ApJS, in press Wyatt, M. C. et al. 2007, ApJ, 658, 569
30-35 (PDF)
S. Clark et al.
An Astrophysical Laboratory: Understanding and Exploiting the Young Massive Cluster Westerlund 1

ADS BibCode:
2015Msngr.159...30C
Section:
Astronomical Science
Author(s)/Affiliation(s):
Clark, S.; Negueruela, I.; Ritchie, B.; Najarro, P.; Langer, N.; Crowther, P.; Bartlett, L.; Fenech, D.; González-Fernández, C.; Goodwin, S.; Lohr, M.; Prinja, R.
AA(Department of Physics and Astronomy, The Open University, Milton Keynes, United Kingdom) AB(Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante, Spain) AC(Department of Physics and Astronomy, The Open University, Milton Keynes, United Kingdom) AD(Departamento de Astrofísica, Centro de Astrobiología; CSIC-INTA), Madrid, Spain) AE(Argelander Institut für Astronomie, Bonn, Germany) AF(Department of Physics and Astronomy, University of Sheffield, United Kingdom) AG(Astrophysics, Cosmology and Gravity Centre (ACGC), Astronomy Department, University of Cape Town, South Africa) AH(Department of Physics & Astronomy, University College London, United Kingdom) AI(Institute of Astronomy, University of Cambridge, United Kingdom) AJ(Department of Physics and Astronomy, University of Sheffield, United Kingdom) AK(Department of Physics and Astronomy, The Open University, Milton Keynes, United Kingdom) AL(Department of Physics & Astronomy, University College London, United Kingdom)
Abstract:
Westerlund 1 provides a unique opportunity to probe the physics of massive stars, from birth to death and beyond, as well as the formation and evolution of a super star cluster that appears destined to evolve into a globular cluster. We highlight the result of current studies of this cluster, its diverse stellar constituents and immediate environment, concluding with a summary of future research avenues enabled by ESO facilities.
References:
Arroyo-Torres, B. et al. 2015, A&A, in press, arXiv:1501.01560 Blomme, R. et al. 2002, A&A, 382, 921 Clark, J. & Porter, J. 2004, A&A, 427, 839 Clark, J. et al. 2005, A&A, 545, 949 Clark, J. et al. 2008, A&A, 477, 147 Clark, J., Ritchie, B. & Negueruela, I. 2010, A&A, 516, A78 Clark, J. et al. 2011, A&A, 531, A28 Clark, J., Ritchie, B. & Negueruela, I. 2013, A&A, 560, A11 Clark, J. et al. 2014, A&A, 565, A90 Crowther, P. et al. 2006, MNRAS, 372, 1407 Davies, B. et al. 2012, MNRAS, 419, 1871 Dougherty, S. et al. 2010, A&A, 511, A58 de Mink, S. et al. 2014, ApJ, 782, 7 Evans, C. et al. 2011, A&A, 530, A108 Kudryavtseva, N. et al. 2012, ApJ, 750, L44 Muno, M. et al. 2006, ApJ, 636, L41 Negueruela, I., Clark, J. & Ritchie, B. 2010, A&A, 516, 78 Negueruela, I. et al. 2011, A&A, 528, A59 Ohm, S., Hinton, J. A. & White, R. 2013, MNRAS, 434, 2289 Ritchie, B. et al. 2009, A&A, 507, 1585 Saio, H., Georgy, C. & Meynet, G. 2013, MNRAS, 433, 1246 Sana, H. et al. 2013, A&A, 550, A107 Schneider, F. et al. 2014, ApJ, 780, 117 Walborn, N. & Blades, J. 1997, ApJS, 112, 457
36-40 (PDF)
M. Zoccali et al.
The GIRAFFE Inner Bulge Survey (GIBS)

ADS BibCode:
2015Msngr.159...36Z
Section:
Astronomical Science
Author(s)/Affiliation(s):
Zoccali, M.; Gonzalez, O. A.; Vasquez, S.; Hill, V.; Rejkuba, M.; Valenti, E.; Renzini, A.; Rojas-Arriagada, A.; Babusiaux, C.; Brown, T.; Minniti, D.; McWilliam, A.
AA(Instituto de Astrofísica, Pontificia Universidad Católica de Chile, Santiago, Chile; The Millennium Institute of Astrophysics, Chile) AB(ESO) AC(Instituto de Astrofísica, Pontificia Universidad Católica de Chile, Santiago, Chile; The Millennium Institute of Astrophysics, Chile) AD(Université de Nice Sophia Antipolis, CNRS, France) AE(ESO; Excellence Cluster Universe, Garching, Germany) AF(ESO) AG(INAF–Osservatorio di Padova, Italy) AH(Université de Nice Sophia Antipolis, CNRS, France) AI(GEPI, Observatoire de Paris, France) AJ(Space Telescope Science Institute, Baltimore, USA) AK(The Millennium Institute of Astrophysics, Chile; Departamento de Ciencias Fisicas, Universidad Andres Bello, Chile; Vatican Observatory, Italy) AL(Carnegie Institute of Washington, Pasadena, USA)
Abstract:
The GIRAFFE Inner Bulge Survey (GIBS) is a spectroscopic survey of ~ 6500 core helium burning (red clump) stars in the Milky Way Bulge, carried out with the FLAMES GIRAFFE spectrograph at the VLT. The aim of the GIBS survey is to derive the metallicity and radial velocity distributions of Bulge stars, across 31 fields in the region of Galactic longitude range –10° to +10° and latitude range –10° to +5°. This is the area also mapped by the VISTA Variables in the Vía Láctea (VVV) ESO Public Survey.
References:
Blitz, L. & Spergel, D. N. 1991, ApJ, 379, 631 Castelli, F. & Kurucz, R. F. 2004, astro-ph/0405087 Dékány, I. et al. 2013, ApJ, 776, L19 Emsellem, E. et al. 2004, MNRAS, 352, 721 Freeman, K. et al. 2013, MNRAS, 428, 3660 Gonzalez, O. A. et al. 2011, A&A, 530, A54 Gonzalez, O. A. et al. 2012, A&A, 543, A13 Gonzalez, O. A. et al. 2013, A&A, 552, A110 Hill, V. et al. 2011, A&A, 534, A80 Howard, C. D. et al. 2009, ApJ, 702, L153 Martinez-Valpuesta, I. et al. 2006, ApJ, 637, 214 Minniti, D. et al. 2010, New Astronomy, 15, 433 Mucciarelli, A. et al. 2013, ApJ, 766, 78 Rich, R. M. et al. 2007, ApJ, 658, L29 Rich, R. M. et al. 2012, ApJ, 746, 59 Sánchez, S. F. et al. 2012, A&A, 538, 8 Soszynski, I. 2014, Acta Astronomica, 64, 177 Vásquez, S. et al. 2013, A&A, 555, A91 Zoccali, M. et al. 2014, A&A, 562, A6
41-45 (PDF)
B. Shahzamanian et al.
Variable and Polarised Near-infrared Emission from the Galactic Centre

ADS BibCode:
2015Msngr.159...41S
Section:
Astronomical Science
Author(s)/Affiliation(s):
Shahzamanian, B.; Eckart, A.; Valencia-S., M.; Witzel, G.; Zamaninasab, M.; Zajaček, M.; Sabha, N.; García-Marín, M.; Karas, V.; Peissker, F.; Karssen, G. D.; Parsa, M.; Grosso, N.; Mossoux, E.; Porquet, D.; Jalali, B.; Horrobin, M.; Buchholz, R.; Dovčiak, M.; Kunneriath, D.; Bursa, M.; Zensus, A.; Schödel, R.; Moultaka, J.; Straubmeier, C.
AA(I. Physikalisches Institut der Universität zu Köln, Germany; Max-Planck-Institut für Radioastronomie, Bonn, Germany) AB(I. Physikalisches Institut der Universität zu Köln, Germany; Max-Planck-Institut für Radioastronomie, Bonn, Germany) AC(I. Physikalisches Institut der Universität zu Köln, Germany) AD(Department of Physics and Astronomy, University of California, Los Angeles, USA) AE(Max-Planck-Institut für Radioastronomie, Bonn, Germany) AF(I. Physikalisches Institut der Universität zu Köln, Germany; Max-Planck-Institut für Radioastronomie, Bonn, Germany; Astronomical Institute of the Academy of Sciences, Prague, Czech Republic) AG(I. Physikalisches Institut der Universität zu Köln, Germany) AH(I. Physikalisches Institut der Universität zu Köln, Germany) AI(Astronomical Institute of the Academy of Sciences, Prague, Czech Republic) AJ(I. Physikalisches Institut der Universität zu Köln, Germany) AK(I. Physikalisches Institut der Universität zu Köln, Germany) AL(I. Physikalisches Institut der Universität zu Köln, Germany) AM(Observatoire Astronomique de Strasbourg, Université de Strasbourg, CNRS, UMR 7550, Strasbourg, France) AN(Observatoire Astronomique de Strasbourg, Université de Strasbourg, CNRS, UMR 7550, Strasbourg, France) AO(Observatoire Astronomique de Strasbourg, Université de Strasbourg, CNRS, UMR 7550, Strasbourg, France) AP(I. Physikalisches Institut der Universität zu Köln, Germany) AQ(I. Physikalisches Institut der Universität zu Köln, Germany) AR(I. Physikalisches Institut der Universität zu Köln, Germany) AS(Astronomical Institute of the Academy of Sciences, Prague, Czech Republic) AT(Astronomical Institute of the Academy of Sciences, Prague, Czech Republic) AU(Astronomical Institute of the Academy of Sciences, Prague, Czech Republic) AV(Max-Planck-Institut für Radioastronomie, Bonn, Germany; I. Physikalisches Institut der Universität zu Köln, Germany) AW(Instituto de Astrofísica de Andalucía (CSIC), Granada, Spain) AX(Université de Toulouse III – CNRS – IRAP, Observatiore Midi-Pyrénées, France) AY(I. Physikalisches Institut der Universität zu Köln, Germany)
Abstract:
Infrared observations of the Galactic Centre (GC) provide a unique opportunity to study stellar and bow-shock polarisation effects in a dusty environment. For the infrared counterpart of the supermassive black hole Sgr A* these observations reveal new insights into the physical processes at work. The observations were carried out with NACO in the Ks-band (2.2 µm) from 2004 to 2012 and several linearly polarised flares were observed during these years. We find that the distribution of polarised flux density is closely related to the single-state power-law distribution of the total flux densities. A typical polarisation degree of the order of 10–20% and a preferred polarisation angle of 13° ± 15° are derived, likely linked to the intrinsic orientation of the Sgr A* system. We discuss different scenarios for the accretion process for the Sgr A* system based on our findings.
References:
Bower, G. C. et al. 2014, ApJ, 790, 1 Bremer, M. et al. 2011, A&A, 532, A26 Buchholz, R. M. et al. 2013, A&A, 557, A82 Buchholz, R. M. et al. 2011, A&A, 534, A117 Eckart, A. et al. 2012, Journal of Physics Conference Series, 372, 012022 Eckart, A. et al. 2014a, in IAU Symposium, Vol. 303, eds. Sjouwerman, L. O., Lang, C. C. & Ott, J., 269 Eckart, A. et al. 2013, A&A, 551, A18 Eckart, A. et al. 2006, A&A, 455, 1 Eckart, A. et al. 2014b, The Astronomer’s Telegram, 6285, 1 Gillessen, S. et al. 2012, Nature, 481, 51 Jalali, B. et al. 2014, MNRAS, 444, 1205 Li, Z., Morris, M. R. & Baganoff, F. K. 2013, ApJ, 779, 154 Meyer, L. et al. 2014, in IAU Symposium, eds. Sjouwerman L. O., Lang C. C. & Ott J., Vol. 303, 264 Muzíc, K. et al. 2010, A&A, 521, A13 Shahzamanian, B. et al. 2014, A&A, in press, arXiv:1411.0006 Valencia-S., M. et al. 2015, ApJ, 800, 125 Witzel, G. et al. 2012, ApJS, 203, 18 Witzel, G. et al. 2011, A&A, 525, A130 Witzel, G. et al. 2014, ApJ, 796, L8 Zajaček, M., Karas, V. & Eckart, A. 2014, A&A, 565, A17 Zamaninasab, M. et al. 2010, A&A, 510, A3
46-50 (PDF)
M. Cantiello et al.
VEGAS-SSS: A VST Programme to Study the Satellite Stellar Systems around Bright Early-type Galaxies

ADS BibCode:
2015Msngr.159...46C
Section:
Astronomical Science
Author(s)/Affiliation(s):
Cantiello, M.; Capaccioli, M.; Napolitano, N.; Grado, A.; Limatola, L.; Paolillo, M.; Iodice, E.; Romanowsky, A. J.; Forbes, D. A.; Raimondo, G.; Spavone, M.; La Barbera, F.; Puzia, T. H.; Schipani, P.
AA(INAF–Osservatorio Astronomico di Teramo, Italy) AB(Dipartimento di Fisica, Universitá di Napoli Federico II, Italy; INAF–Osservatorio Astronomico di Capodimonte Napoli, Italy
) AC(INAF–Osservatorio Astronomico di Capodimonte Napoli, Italy
) AD(INAF–Osservatorio Astronomico di Capodimonte Napoli, Italy
) AE(INAF–Osservatorio Astronomico di Capodimonte Napoli, Italy
) AF(Dipartimento di Fisica, Universitá di Napoli Federico II, Italy; Agenzia Spaziale Italiana — Science Data Center, Roma, Italy) AG(INAF–Osservatorio Astronomico di Capodimonte Napoli, Italy
) AH(University of California Observatories, Santa Cruz, USA
; Department of Physics and Astronomy, San José State University, USA
) AI(Centre for Astrophysics & Supercomputing, Swinburne University, Hawthorn, Australia
) AJ(INAF–Osservatorio Astronomico di Teramo, Italy) AK(INAF–Osservatorio Astronomico di Capodimonte Napoli, Italy
) AL(INAF–Osservatorio Astronomico di Capodimonte Napoli, Italy
) AM(Institute of Astrophysics, Pontificia Universidad Católica de Chile, Santiago, Chile
; National Research Council Canada, Herzberg Institute of Astrophysics, Victoria, Canada) AN(INAF–Osservatorio Astronomico di Capodimonte Napoli, Italy
)
Abstract:
The VEGAS-SSS programme is devoted to studying the properties of small stellar systems (SSSs) in and around bright galaxies, built on the VLT Survey Telescope early-type galaxy survey (VEGAS), an ongoing guaranteed time imaging survey distributed over many semesters (Principal Investigator: Capaccioli). On completion, the VEGAS survey will have collected detailed photometric information of ~ 100 bright early-type galaxies to study the properties of diffuse light (surface brightness, colours, surface brightness fluctuations, etc.) and the distribution of clustered light (compact ''small'' stellar systems) out to previously unreached projected galactocentric radii. VEGAS-SSS will define an accurate and homogeneous dataset that will have an important legacy value for studies of the evolution and transformation processes taking place in galaxies through the fossil information provided by SSSs.
References:
Arnold, J. A. et al. 2011, ApJ, 736, L26 Brodie, J. et al. 2012, ApJ, 759, L33 Cantiello, M. et al. 2013, A&A, 552, 106 Cantiello, M. et al. 2014a, A&A, 564, L3 Cantiello, M. et al. 2014b, A&A, in press, DOI: 10.1051/0004-6361/201425165 Capaccioli, M. & Schipani, P. 2011, The Messenger, 146, 2 Forbes, D. A. et al. 2013, MNRAS, 435, L6 Goudfrooij, P. et al. 2007, AJ, 133, 2737 Grado, A. et al. 2012, Mem. S. A. It. S., 19, 362 Harris, W. et al. 2014, ApJ, 797, 128 Jennings, Z. G. et al. 2014, AJ, 148, 32 Jordan, A. 2004, ApJ, 613, L117 Jordan, A. et al. 2007, ApJS, 171, 101 Larsen, S. S. 1999, A&AS, 139, 393 West, M. J. et al. 1995, ApJ, 453, L77

Astronomical News

52-56 (PDF)
H. Boffin et al.
Report on the ESO Workshop ''Astronomy at High Angular Resolution''

ADS BibCode:
2015Msngr.159...52B
Section:
Astronomical News
Author(s)/Affiliation(s):
Boffin, H.; Schmidtobreick, L.; Hussain, G.; Berger, J.-Ph.
AA(ESO) AB(ESO) AC(ESO) AD(ESO)
Abstract:
A workshop took place in Brussels in 2000 on astrotomography, a generic term for indirect mapping techniques that can be applied to a huge variety of astrophysical systems, ranging from planets, single stars and binaries to active galactic nuclei. It appeared to be timely to revisit the topic given the many past, recent and forthcoming improvements in telescopes and instrumentation. We therefore decided to repeat the astrotomography workshop, but to put it into the much broader context of high angular resolution astronomy. Many techniques, from lucky and speckle imaging, adaptive optics to interferometry, are now widely employed to achieve high angular resolution and they have led to an amazing number of new discoveries. A summary of the workshop themes is presented.
References:
Baron, F. et al. 2012, SPIE, 8445, 84451E Boffin, H. M. J., Steeghs, D. & Cuypers, J. 2001, Astrotomography, Indirect Imaging Methods in Observational Astronomy, LNP Series 573, Springer Boffin, H. M. J. et al. 2014, The Messenger, 156, 35 Eisenhauer, F. et al. 2011, The Messenger, 143, 16 Lopez, B. et al. 2014, The Messenger, 157, 5 Merkle, F. et al. 1989, The Messenger, 58, 1 Milli, J. et al. 2014, arXiv:1407.2539 Monnier, J. D. et al. 2014, Proc. SPIE, 9146, 91461Q Rengaswamy, S. et al. 2014, The Messenger, 155, 12 Romanova, M. M. et al. 2011, MNRAS, 411, 915 Schaefer, G. H. et al. 2014, Nature, 515, 234
57-58 (PDF)
P. Roche
New President of Council

ADS BibCode:
2015Msngr.159...57R
Section:
Astronomical News
Author(s)/Affiliation(s):
Roche, P.
AA(Department of Physics, University of Oxford, United Kingdom)
58-60 (PDF)
B. Husemann, T. Zafar
Fellows at ESO

ADS BibCode:
2015Msngr.159...58.
Section:
Astronomical News
Author(s)/Affiliation(s):
Husemann, B.; Zafar, T.
AA(ESO) AB(ESO)
60-61 (PDF)
K. Tristram
Staff at ESO

ADS BibCode:
2015Msngr.159...60.
Section:
Astronomical News
Author(s)/Affiliation(s):
Tristram, K.
AA(ESO)
62-62 (PDF)
F. Comerón
In Memoriam Luis Wendegass

ADS BibCode:
2015Msngr.159...62C
Section:
Astronomical News
Author(s)/Affiliation(s):
Comerón, F.
AA(ESO)
62-62 (PDF)
ESO
Personnel Movements

ADS BibCode:
2015Msngr.159...62.
Section:
Astronomical News
Author(s)/Affiliation(s):
ESO
AA(ESO)
63-63 (PDF)
ESO
ESO Studentship Programme 2015

ADS BibCode:
2015Msngr.159...63.
Section:
Astronomical News
Author(s)/Affiliation(s):
ESO
AA(ESO)

Annual Index

64-67 (PDF)
ESO
Annual Index 2014

ADS BibCode:
2015Msngr.159...64.
Section:
Annual Index
Author(s)/Affiliation(s):
ESO
AA(ESO)