Radial Velocities for 889 Late‐Type Stars

We report radial velocities for 844 FGKM-type main sequence and subgiantstars and 45 K giants, most of which had either low-precision velocitymeasurements or none at all. These velocities differ from the standard stars ofUdry et al. by 0.035 km/s (RMS) for the 26 FGK standard stars in common. Thezero-point of our velocities differs from that of Udry et al.: (V_present -V_Udry) = +0.053 km/s. Thus these new velocities agree with the best knownstandard stars both in precision and zero-point, to well within 0.1 km/s. Nonetheless, both these velocities and the standards suffer from threesources of systematic error, namely, convective blueshift, gravitationalredshift, and spectral type mismatch of the reference spectrum. Thesesystematic errors are here forced to be zero for G2V stars by using the Sun asreference, with Vesta and day sky as proxies. But for spectral types departingfrom solar, the systematic errors reach 0.3 km/s in the F and K stars and 0.4km/s in M dwarfs. Multiple spectra were obtained for all 889 stars during four years, and 782of them exhibit velocity scatter less than 0.1 km/s. These stars may serve asradial velocity standards if they remain constant in velocity. We found 11 newspectroscopic binaries and report orbital parameters for them.Comment: 76 pages, 23 figures, 4 tables, uses aastex.st