Observations of Candidate z=1.54 Quasar Host Clusters

Abstract

We present new data on several z=1.54 radio-loud quasar fields from a sample of 31 at z=1-2 in which we have previously identified an excess population of predominantly red galaxies. Narrow-band H-alpha observations detect five candidate galaxies at the quasar redshifts in three fields totaling 10.156 arcmin^2, a surface density 30 times higher than in previous surveys, even targeted ones. SCUBA observations of three fields detect at least one candidate quasar-associated galaxy. Many galaxies with SEDs indicating considerable dust are not detected, but the limits are only sufficient to rule out hyperluminous infrared galaxies. Finally, quantitative photometric redshifts and SED fits are presented for one "J-band dropout" galaxy with J-K>2.5 which is confirmed to be very dusty (E(B-V)~=0.5) and background to the quasar at >99.9% confidence.