Abstract

We studied the clustering properties and multiwavelength spectral energy distributions of a complete sample of 162 Ly?-emitting (LAE) galaxies at z ? 3.1 discovered in deep narrowband MUSYC imaging of the Extended Chandra Deep Field-South. LAEs were selected to have observed frame equivalent widths >80 Å and emission line fluxes >1.5 × 10 -17 ergs cm -2 s -1. Only 1% of our LAE sample appears to host AGNs. The LAEs exhibit a moderate spatial correlation length of r 0 = 3.6 -1.0 +0.8 Mpc, corresponding to a bias factor b = 1.7 -0.4 +0.3, which implies median dark matter halo masses of log 10M med = 10.9 -0.9 +0.5 M ?. Comparing the number density of LAEs, 1.5 ± 0.3 × 10 -3 Mpc -3, with the number density of these halos finds a mean halo occupation ?1%-10%. The evolution of galaxy bias with redshift implies that most z = 3.1 LAEs evolve into present-day galaxies with L < 2.5L*, whereas other z > 3 galaxy populations typically evolve into more massive galaxies. Halo merger trees show that z = 0 descendants occupy halos with a wide range of masses, with a median descendant mass close to that of L*. Only 30% of LAEs have sufficient stellar mass (>? 3 × 10 9 M ?) to yield detections in deep Spitzer IRAC imaging. A two-population SED fit to the stacked UBVRIzJK+[3.6, 4.5, 5.6, 8.0] ?m fluxes of the IRAC-undetected objects finds that the typical LAE has low stellar mass (1.0 -0.4 +0.6 × 10 9 M ?), moderate star formation rate (2 ± 1 M ? yr -1),ayoung component age of 20 -10 +30 Myr, and little dust (A V < 0.2). The bestfit model has 20% of the mass in the young stellar component, but models without evolved stars are also allowed. © 2007. The American Astronomical Society. All rights reserved.