Results from upgrades to the radial velocity instrument, ET, at the KPNO 2.1m

A radial velocity (RV) survey Instrument, Exoplanet Tracker (ET), has been commissioned at the Kitt Peak 2.1m telescope. It is a fiber-fed, fixed-delay Michelson interferometer followed by a medium resolution volume phase holographic spectrograph (operating at R ∼5000) for the visual band, and is planned to be opened to the public for RV related research in 2005. Since 2002 the measured total throughput of ET from above the atmosphere to the detector has been improved to about 18% (or 50% for the instrument itself from the fiber input to the detector), ∼5 times higher than the current cross-dispersed echelle spectrometers for Doppler planet searches. We present new preliminary results from our improved version of ET, with 600Å wavelength coverage, showing RV measurements for HD 130322 (V=8.05), a known planet-bearing star, using 15 min exposures. A best short-term Doppler precision of 2.9ms ^-1 has been achieved with this new instrument. We will start a pilot planet search of around 500 V=8-9 mag. stars with the 2.1m telescope in the Spring of 2005, and a multiple object RV feasibility study will also be conducted at the Sloan 2.5m wide field telescope in Spring 2005.