Share Email Print
cover

Proceedings Paper

SPHERE IRDIS and IFS astrometric strategy and calibration
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

We present the current results of the astrometric characterization of the VLT planet finder SPHERE over 2 years of on-sky operations. We first describe the criteria for the selection of the astrometric fields used for calibrating the science data: binaries, multiple systems, and stellar clusters. The analysis includes measurements of the pixel scale and the position angle with respect to the North for both near-infrared subsystems, the camera IRDIS and the integral field spectrometer IFS, as well as the distortion for the IRDIS camera. The IRDIS distortion is shown to be dominated by an anamorphism of 0.60±0.02% between the horizontal and vertical directions of the detector, i.e. 6 mas at 1 arcsec. The anamorphism is produced by the cylindrical mirrors in the common path structure hence common to all three SPHERE science subsystems (IRDIS, IFS, and ZIMPOL), except for the relative orientation of their field of view. The current estimates of the pixel scale and North angle for IRDIS are 12.255±0.009 milliarcseconds/pixel for H2 coronagraphic images and -1.70±0.08°. Analyses of the IFS data indicate a pixel scale of 7.46±0.02 milliarcseconds/pixel and a North angle of -102.18±0.13°. We finally discuss plans for providing astrometric calibration to the SPHERE users outside the instrument consortium.

Paper Details

Date Published: 9 August 2016
PDF: 12 pages
Proc. SPIE 9908, Ground-based and Airborne Instrumentation for Astronomy VI, 990834 (9 August 2016); doi: 10.1117/12.2233013
Show Author Affiliations
Anne-Lise Maire, Max-Planck-Institut für Astronomie (Germany)
Maud Langlois, Ctr. de Recherche Astrophysique de Lyon, Univ. Lyon, Univ. Lyon 1, CNRS (France)
Kjetil Dohlen, Lab. d'Astrophysique de Marseille (France)
Anne-Marie Lagrange, Institut de Planétologie et d’Astrophysique de Grenoble (France)
Raffaele Gratton, INAF - Osservatorio Astronomico di Padova (Italy)
Gaël Chauvin, Institut de Planétologie et d’Astrophysique de Grenoble (France)
Silvano Desidera, INAF - Osservatorio Astronomico di Padova (Italy)
Julien H. Girard, European Southern Observatory (Chile)
Institut de Planétologie et d’Astrophysique de Grenoble (France)
Julien Milli, European Southern Observatory (Chile)
Institut de Planétologie et d’Astrophysique de Grenoble (France)
Arthur Vigan, Lab. d'Astrophysique de Marseille (France)
Gerard Zins, European Southern Observatory (Chile)
Philippe Delorme, Institut de Planétologie et d’Astrophysique de Grenoble (France)
Jean-Luc Beuzit, Institut de Planétologie et d’Astrophysique de Grenoble (France)
Riccardo U. Claudi, INAF - Osservatorio Astronomico di Padova (Italy)
Markus Feldt, Max-Planck-Institut für Astronomie (Germany)
David Mouillet, Institut de Planétologie et d’Astrophysique de Grenoble (France)
Pascal Puget, Institut de Planétologie et d’Astrophysique de Grenoble (France)
Massimo Turatto, INAF - Osservatorio Astronomico di Padova (Italy)
François Wildi, Observatoire de Genève (Switzerland)


Published in SPIE Proceedings Vol. 9908:
Ground-based and Airborne Instrumentation for Astronomy VI
Christopher J. Evans; Luc Simard; Hideki Takami, Editor(s)

© SPIE. Terms of Use
Back to Top