Caltech Faint Galaxy Redshift Survey. IX. Source Detection and Photometry in the Hubble Deep Field Region

Detection and photometry of sources in the U n , G , , and K s bands in a 9 × 9 arcmin 2 region of the sky, centered on the Hubble Deep Field, are described. The data permit construction of complete photometric catalogs to roughly U n = 25, G = 26, = 25.5, K s = 20 mag and significant photometric measurements somewhat fainter. The galaxy number density is 1.3 × 10 5 deg -2 to = 25.0 mag. Galaxy number counts have slopes d log N / dm = 0.42, 0.33, 0.27, and 0.31 in the U n , G , , and K s bands, consistent with previous studies and the trend that fainter galaxies are, on average, bluer. Galaxy catalogs selected in the and K s bands are presented, containing 3607 and 488 sources in field areas of 74.8 and 59.4 arcmin 2 , to = 25.5 and K s = 20 mag.