The First Release COSMOS Optical and Near‐IR Data and Catalog

TLDR

The paper presents COSMOS survey imaging and photometry across 15 bands from 0.3 to 2.4 µm. The data were obtained with Subaru, KPNO, CTIO, and CFHT telescopes, and calibrated to better than 1 % relative accuracy and 2 % absolute color accuracy using galaxy spectra. The catalog achieves 6 % absolute photometric accuracy, with stellar and galaxy colors and counts matching expectations, and panchromatic number counts support evolving galaxy populations and cosmological geometry.

Abstract

We present imaging data and photometry for the COSMOS survey in 15 photometric bands between 0.3 and 2.4 μm. These include data taken on the Subaru 8.3 m telescope, the KPNO and CTIO 4 m telescopes, and the CFHT 3.6 m telescope. Special techniques are used to ensure that the relative photometric calibration is better than 1% across the field of view. The absolute photometric accuracy from standard-star measurements is found to be 6%. The absolute calibration is corrected using galaxy spectra, providing colors accurate to 2% or better. Stellar and galaxy colors and counts agree well with the expected values. Finally, as the first step in the scientific analysis of these data we construct panchromatic number counts which confirm that both the geometry of the universe and the galaxy population are evolving.