2003AJ....125.1053H

Two micron broad- and narrowband imaging with the Gemini North Telescope of five z∼4.7 QSOs has resolved both the host galaxies and [O II] emission-line gas. The resolved fluxes of the host galaxies fall within the extrapolated spread of the K-z relationship for radio galaxies at lower redshifts, and their resolved morphology is irregular. The [O II] images indicate knots coincident with many continuum features and also some bright jetlike features near the nucleus. The line emission total fluxes indicate overall equivalent widths of 5-10 Å at rest wavelengths. Two of the QSOs are in a local environment of faint galaxies of similar magnitude to the hosts, and three have nearby galaxies with excess narrowband flux, which would be [O II] if they are at the QSO redshift.