Performances tests on the SPHERE-IFS

TL;DR

This paper reports on performance tests of the SPHERE-IFS instrument, demonstrating its potential to detect faint exoplanets and perform precise astrometry, with identified issues for further improvement.

Contribution

It provides the first detailed performance evaluation of the SPHERE-IFS instrument under realistic conditions, highlighting its capabilities and challenges.

Findings

Contrast down to 5x10^{-7} achieved

Astrometry at sub-milliarcsecond level possible

Critical issues identified for performance enhancement

Abstract

Until now, just a few extrasolar planets (~30 out of 860) have been found through the direct imaging method. This number should greatly improve when the next generation of High Contrast Instruments like Gemini Planet Imager (GPI) at Gemini South Telescope or SPHERE at VLT will became operative at the end of this year. In particular, the Integral Field Spectrograph (IFS), one of the SPHERE subsystems, should allow a first characterization of the spectral type of the found extrasolar planets. Here we present the results of the last performance tests that we have done on the IFS instrument at the Institut de Planetologie et d'Astrophysique de Grenoble (IPAG) in condition as similar as possible to the ones that we will find at the telescope. We have found that we should be able to reach contrast down to 5x10$^{-7}$ and make astrometry at sub-mas level with the instrument in the actual conditions. A number of critical issues have been identified. The resolution of these problems could allow to further improve the performance of the instrument.