Near-infrared Imaging of Early-Type Galaxies. II. Global Photometric Parameters

An imaging survey of 341 nearby early-type galaxies in the near-infrared K-band atmospheric window (2.2 μm) is described. The galaxies primarily reside in 13 nearby rich clusters (85%), while some additional galaxies are drawn from loose groups (12%) and the general field (3%). Surface photometry was measured for the entire sample. Detailed corrections were derived from an extensive grid of seeing-convolved r^1/4 models and then applied to the isophotal surface brightness, aperture magnitude, and ellipticity profiles. Global photometric parameters were derived from this seeing-corrected photometry. More than 25% of the sample has been observed at least twice, and these repeat measurements demonstrate the small internal uncertainties on the derived global photometric parameters. Extensive comparisons with aperture photometry from the literature demonstrate that the photometric system is fully consistent with other photometric systems to <=0.01 mag and confirm the estimates of internal random uncertainties. Additional global parameters are drawn from the literature in a homogeneous manner in order to construct a large catalog of galaxy properties: 95% of the galaxies have a velocity dispersion, 69% have a Mg₂ index, 80% have an optical r_eff and <μ>_eff, 82% have a D_n, and 81% have a derived optical - infrared color measurement. This large data set provides excellent source material for investigations of the physical origins of the global scaling relations of early-type galaxies, velocity fields in the local universe, and comparisons to higher redshift early-type galaxies.