Low-Luminosity Companions to Nearby Stars: Status of the 2MASS Data Search

We present 2MASS discoveries of four L and T dwarf companions to nearby stars. Using spectral types of the companions and age estimates of the primaries, we estimate masses for these discoveries and compare them to four other L and T dwarf companions from the literature. Temperatures range from ~2000 to ~750 K, ages range from ~0.2 to ~3 Gyr, and masses range from ~0.035 to ~0.075 MO.