HDF-North serendipitously galaxies

Among the identified objects are five candidate Ly{alpha} emitters at z>~5, a galaxy cluster at z=0.85, and a Chandra source with a heretofore undetermined redshift of z=2.011. We report redshifts for 25 galaxies in the central HDF, 13 of which had no prior published spectroscopic redshift.

Of the remaining 49 galaxies, 30 are located in the single-orbit HDF flanking fields. We discuss the redshift distribution of the serendipitous sample, which contains galaxies in the range 0.10<z<5.77 with a median redshift of z=0.85, and we present strong evidence for redshift clustering. By comparing our spectroscopic redshifts with optical/IR photometric studies of the HDF, we find that photometric redshifts are in most cases capable of producing reasonable predictions of galaxy redshifts.