The 2MASS Red AGN Survey

Abstract

The Two Micron All Sky Survey (2MASS) is a highly uniform digital imaging survey of the entire sky in three near infrared bands. The 2MASS catalogs provide unprecedented uniform photometric data for large samples of AGN discovered at other wavelengths, and also form the basis to search for previously unknown, obscured AGN. We present the results of a highly efficient near infrared color-based AGN survey using 2MASS that has already discovered 210 new, red AGN and QSOs. The extrapolated surface density of the 2MASS red AGN is ~0.5 deg-2 for Ks < 14.5 mag, and the space density of the Type 1 AGN inferred from the Ks luminosity function is at least as large as that of optical- and UV-selected QSO samples. The ratio of Type 1 to Type 2 AGN among the newly discovered objects is 2:1, similar to proportions found in X-ray and deep ISO surveys, but the inverse of that found in IRAS surveys. The median redshift of the new 2MASS red AGN sample is z=0.23, and all but three have z < 0.7. The color distribution, polarization properties and preliminary X-ray data suggest that most of the 2MASS-discovered AGN are red because of obscuration by dust in and around their nuclei. Show more