GRAVITY Collaboration, F. Widmann, X. Haubois N. Schuhler, O. Pfuhl, F. Eisenhauer, S. Gillessen, N. Aimar, A. Amorim, M. Bauböck, J. B. Berger, H. Bonnet, G. B… 展开作者
GRAVITY Collaboration, F. Widmann, X. Haubois N. Schuhler, O. Pfuhl, F. Eisenhauer, S. Gillessen, N. Aimar, A. Amorim, M. Bauböck, J. B. Berger, H. Bonnet, G. Bourdarot, W. Brandner, Y. Clénet, R. Davies, P. T. de Zeeuw, J. Dexter, A. Drescher, A. Eckart, H. Feuchtgruber, N. M. Förster Schreiber, P. Garcia, E. Gendron, R. Genzel, M. Hartl, F. Haußmann, G. Heißel, T. Henning, S. Hippler, M. Horrobin, A. Jiménez-Rosales, L. Jocou, A. Kaufer, P. Kervella, S. Lacour, V. Lapeyrère, J. -B. Le Bouquin, P. Léna, D. Lutz, F. Mang, N. More, M. Nowak, T. Ott, T. Paumard, K. Perraut, G. Perrin, S. Rabien, D. Ribeiro, M. Sadun Bordoni, S. Scheithauer, J. Shangguan, T. Shimizu, J. Stadler, O. Straub, C. Straubmeier, E. Sturm, L. J. Tacconi, F. Vincent, S. D. von Fellenberg, E. Wieprecht, E. Wiezorrek, J. Woillez
The goal of this work is to characterize the polarization effects of the VLTI and GRAVITY. This is needed to calibrate polarimetric observations with GRAVITY for instrumental effects and to understand the systematic error introduced to the astrometry due to birefringence when observing targets with a significant intrinsic polarization. By combining a model of the VLTI light path and its mirrors and dedicated experimental data, we construct a full polarization model of the VLTI UTs and the GRAVITY instrument. We first characterize all telescopes together to construct a UT calibration model for polarized targets. We then expand the model to include the differential birefringence. With this, we can constrain the systematic errors for highly polarized targets. Together with this paper, we publish a standalone Python package to calibrate the instrumental effects on polarimetric observations. This enables the community to use GRAVITY to observe targets in a polarimetric observing mode. We demonstrate the calibration model with the galactic center star IRS 16C. For this source, we can constrain the polarization degree to within 0.4 % and the polarization angle within 5 deg while being consistent with the literature. Furthermore, we show that there is no significant contrast loss, even if the science and fringe-tracker targets have significantly different polarization, and we determine that the phase error in such an observation is smaller than 1 deg, corresponding to an astrometric error of 10 μas. With this work, we enable the use of the polarimetric mode with GRAVITY/UTs and outline the steps necessary to observe and calibrate polarized targets. We demonstrate that it is possible to measure the intrinsic polarization of astrophysical sources with high precision and that polarization effects do not limit astrometric observations of polarized targets.
Beating the confusion limit: The necessity of high angular resolution for probing the physics of Sagittarius A* and its environment: Opportunities for LINC-NIRVANA (LBT), GRAVITY (VLTI) and and METIS (E-ELT)
SIMTERFERE: An optical interferometry simulator for quantifying the coherent flux stability of VLTI/GRAVITY+. Reaching per mill stability: Application to exoplanet spectroscopy
Max-Planck-Institut für Astronomie（马克斯·普朗克天文学研究所）；Fakultät für Physik und Astronomie, Universität Heidelberg（海德堡大学物理与天文学学院）；Max-Planck-Institut für extraterrestrische Physik（马克斯·普朗克地外物理学研究所）；I. Physikalisches Institut, Universität zu Köln（科隆大学第一物理研究所）
First Light for the GRAVITY+ Adaptive Optics: Extreme Adaptive Optics for the Very Large Telescope Interferometer
Max Planck Institute for extraterrestrial Physics（马克斯·普朗克地外物理研究所）；Institute National des Sciences de l’Univers du CNRS (INSU)（法国国家科学研究中心宇宙科学研究所）；Max Planck Institute for Astronomy（马克斯·普朗克天文学研究所）；University of Cologne（科隆大学）；CENTRA - Centro de Astrofisica e Gravitação（中心天体物理学与引力中心）；University of Southampton（南安普顿大学）；Katholieke Universiteit Leuven（荷语鲁汶大学）；University College Dublin（都柏林大学学院）；Universidad Nacional Autónoma de México（墨西哥国立自治大学）；European Southern Observatory（欧洲南方天文台）
Mid-IR Water-Vapor Seeing: Implications for ELT/METIS High-Contrast Imaging from VLTI Data
Indian Institute of Technology Kanpur（坎普尔印度理工学院）；Université de Liège（列日大学）；Australian National University（澳大利亚国立大学）；European Southern Observatory（欧洲南方天文台）；Université Côte d’Azur（蔚蓝海岸大学）；Max-Planck-Institut für Astronomie（马克斯·普朗克天文学研究所）；Leiden University（莱顿大学）；Macquarie University（麦考瑞大学）
