GREGOR AT NIGHT SPECTROGRAPH
GANS is optimised for precise radial velocity measurements. It has a high resolving power of R~60000 with 3 arcsec aperture on sky with a 65 um octagonal fibre and 2-time slicer. The one-shot covered wavelength range is from 470 nm to 680 nm using a 2kx2k CCD with 13 um pixels, with a simultaneous reference spectrum from Fabry-Perot-Etalon. The spectrograph is vacuum enclosed and thermally stabilised. Estimated limiting magnitude will be around V~8-9 with RV ~2 m/s.
GANS is foreseen to be operated in a fully robotic fashion including day-to-night operation shifting. It is ideal for high cadence, long-term observations of selected objects, with main aim at pre- and post-launch observations of PLATO and TESS targets.