TIMMI2: a new multimode mid-infrared instrument for the ESO 3.6-m telescope

TIMMI2 is a focal reducer with variable magnification using a reflective collimator and various camera lenses from Silicon, CdTe, Germanium and KRS-5. The primary operating wavelength is 8-24 microns with limited access also to the 3-5 micron region. Longslit and Echelle spectroscopy up to a resolving power of 1000 are implemented with grisms. A cryogenic wire grid polarizer allows for imaging polarimetry. TIMMI2 uses a 240 X 320 As:Si detector array and is cooled by a 2 stage Gifford-McMahon cooler. Maximum field is 72 X 96 arcsec. TIMMI2 has 5 internal cryogenic functions and one external wheel holding calibration targets. TIMMI2 will be interfaced to the 3.6m telescope with a special IR adapter allowing wheel holding registration of the IR images with respect to astrometric reference frames. The instrument design, electronics and results from laboratory test will be presented. Sensitivity estimates as well as an outlook on possible astronomical programs will be given.