Infrared observations of nebular emission lines from galaxies at z ≌ 3

摘要

We present the first results from a program of near-infrared spectroscopy aimed at studying the fam- iliar rest-frame optical emission lines from the H II regions of Lyman break galaxies at z ≌3. By target- ing redshifts that bring the lines of interest of interest into gaps between the strong OH sky emission, we have been successful in detecting Balmer and [O III] emission lines in all five galaxies observed so far with CGS4 on UKIRT. the typical line fluxes are a few times 10~-17 ergs s~-1 cm~-2, approximately 1 order of mag- nitude lower than the limits reached with wide-field narrowband imaging surveys.