Cryogenic test results of the SCALES focal plane coronagraph mechanism

We present preliminary laboratory cryogenic test results for the Coronagraph Slide mechanism, which allows observers the choice of up to 4 coronagraphic focal plane masks when using SCALES (Santa Cruz Array of Lenslets for Exoplanet Spectroscopy). SCALES is a 2-5 micron high-contrast lenslet integral field spectrograph currently undergoing preliminary design for the W. M. Keck Observatory. When deployed behind the Keck Adaptive Optics system, SCALES will be used to detect and characterize a wide variety of exoplanets. To minimize thermal emission, all optical and mechanical components of SCALES are fully cryogenic. The Coronagraph Slide is the first fully cryogenic mechanism for SCALES designed, built, and tested in-house at UCSC with mostly off-the-shelf components.