Supernova / Acceleration Probe: Instrumentation

The Supernova / Acceleration Probe (SNAP) is a space experiment to measure the cosmological parameters and investigate the properties of the dark energy. The SNAP science goals require the control of measurement systematics using high resolution, high signal-to-noise photometric and spectrocopic observations. These science goals drive the design requirements for SNAP instrumentation. We describe an instrument suite which is optimized to meet these stringent requirements. The baseline optic is a diffraction limited, f/10, three-mirror, anastigmatic, 2-meter class telescope with a plate scale of 0.1 arcsec/pixel. The optical imager is a wide field, one square degree, billion pixel CCD mosaic. A high-resolution, near-IR camera consists of a HgCdTe array, with a FOV of 10 square arcminutes, covering the wavelength region from 1 to 1.7 microns. An optical/NIR multi-arm spectrograph system with resolution approximately R=200, comprises the third science instrument. Other instruments include a star tracker able to guide with a stability of within 0.03 arcsec. This project is funded in part by the US DOE and the NSF.