A Search for Lyman Break Galaxies at z > 8 in the NICMOS Parallel Imaging Survey

Abstract

We have selected 14 J-dropout Lyman break galaxy (LBG) candidates with J110 - H160 ≥ 2.5 from the NICMOS Parallel Imaging Survey. This survey consists of 135 arcmin2 of imaging in 228 independent sight lines, reaching average 5 σ sensitivities of J 110 = 25.8 and H160 = 25.6 (AB). Distinguishing these candidates from dust-reddened star-forming galaxies at z ∼ 2-3 is difficult and will require longer wavelength observations. We consider the likelihood that any J-dropout LBGs exist in this survey and find that if L*z= 9.5 is significantly brighter than L*z=6 (a factor of 4), then a few J-dropout LBGs are likely. A similar increase in luminosity has been suggested by Eyles et al. and Yan et al., but the magnitude of this increase is uncertain. © 2007. The American Astronomical Society. All rights reserved.