GYES, A Multifibre Spectrograph for the CFHT

¹ GÉPI, Observatoire de Paris, CNRS, Université Paris Diderot, 5 place Jules Janssen, 92190 Meudon, France
² Observatoire astronomique de Strasbourg, 11 rue de l’Université, 67000 Strasbourg, France
³ Department of Astronomy and Astrophysics, University of Toronto, Toronto, Ontario M5S 3H4, Canada
⁴ University of Oxford, Astrophysics, Department of Physics, Keble Road, Oxford OX1 3RH, UK
⁵ Royal Observatory Belgium Astrometry-Dynamics of Celestial Bodies, Av. Circulaire 3-Ringlaan 3, 1180 Brussels, Belgium
⁶ Université de Nice Sophia Antipolis, CNRS, Observatoire de la Côte d’Azur, Laboratoire Cassiopée, BP. 4229, 06304 Nice Cedex 4, France
⁷ Institute for Astronomy, University of Hawaii at Manoa, 2680 Woodlawn Drive, Honolulu, Hawaii 96822, USA
⁸ LATMOS/IPSL, 11 Bd. d’Alembert, 78280 Guyancourt, France
⁹ Kapteyn Astronomical Institute, Landleven 12, 9747 AD Groningen, The Netherlands
¹⁰ European Southern Observatory, Alonso de Còrdova, 3107 Vitacura - Santiago, Chile
¹¹ Université de Nice Sophia Antipolis, CNRS, Observatoire de la Côte d’Azur, Laboratoire Fizeau, BP. 4229, 06304 Nice Cedex 4, France
¹² Observatoire de Besançon, 41 bis, Avenue de l’Observatoire, BP. 1615, 25010 Besançon Cedex, France
¹³ Observatoire de Bordeaux, 2 avenue de l’Observatoire, 33270 Floirac, France
¹⁴ Department of Physics & Astronomy The University of Victoria, Elliott Building, 3800 Finnerty Road Victoria, BC, V8P 5C2, Canada

Abstract

We have chosen the name of GYES, one of the mythological giants with one hundred arms, offspring of Gaia and Uranus, for our instrument study of a multifibre spectrograph for the prime focus of the Canada-France-Hawaii Telescope. Such an instrument could provide an excellent ground-based complement for the Gaia mission and a northern complement to the HERMES project on the AAT. The CFHT is well known for providing a stable prime focus environment, with a large field of view, which has hosted several imaging instruments, but has never hosted a multifibre spectrograph. Building upon the experience gained at GÉPI with FLAMES-Giraffe and X-Shooter, we are investigating the feasibility of a high multiplex spectrograph (about 500 fibres) over a field of view one degree in diameter. We are investigating an instrument with resolution in the range 15 000 to 30 000, which should provide accurate chemical abundances for stars down to 16th magnitude and radial velocities, accurate to 1 km s^-1 for fainter stars. The study is led by GÉPI-Observatoire de Paris with a contribution from Oxford for the study of the positioner. The financing for the study comes from INSU CSAA and Observatoire de Paris. The conceptual study will be delivered to CFHT for review by October 1st 2010.