ﻻ يوجد ملخص باللغة العربية
We have obtained spectroscopic redshifts using the Keck-I telescope for a sample of 73 submillimeter (submm) galaxies for which precise positions are available. The galaxies lie at redshifts out to z=3.6, with a median redshift of 2.2. The dust-corrected ultraviolet (UV) luminosities of the galaxies rarely hint at their huge bolometric luminosities indicated by their radio/submm emission, underestimating the true luminosity by a median factor of ~100 for SMGs with pure starburst spectra. The 850mu, radio, and redshift data is used to estimate the dust temperatures (<Td>=36+-7 K), and characterize photometric redshifts. We calculate total infrared and bolometric luminosities, construct a luminosity function, and quantify the strong evolution of the submm population across z=0.5-3.5, relative to local IRAS galaxies. We conclude that bright submm galaxies contribute a comparable star formation density to Lyman-break galaxies at z=2-3 and including galaxies below our submm flux limit this population may be the dominant site of massive star formation at this epoch. The rapid evolution of submm galaxies and QSO populations contrasts with that seen in bolometrically lower luminosity galaxy samples selected in the restframe UV, and suggests a close link between submm galaxies and the formation and evolution of the galactic halos which host QSOs. [Abridged].
We have identified 335 galaxy cluster and group candidates spanning 0<z<2, using a 4.5um selected sample of galaxies in a 7.25 deg^2 region in the Spitzer/IRAC Shallow Survey. Using full redshift probability distributions for all galaxies, clusters w
We have used the Submillimeter Array to image a flux limited sample of seven submillimeter galaxies, selected by the AzTEC camera on the JCMT at 1.1 mm, in the COSMOS field at 890um with 2 resolution. All of the sources - two radio-bright and five ra
Using photometric redshifts we determine the galaxy population of the clusters of galaxies Cl0016+16 at z=0.55, Cl1600+41 at z=0.54, Cl1601+42 at z=0.54 and MS1008-1224 at z=0.31. Comparing the clusters, we find no evidence for a universal shape of t
We present a study of the luminosity and color properties of galaxies selected from a sample of 57 low-redshift Abell clusters. We utilize the non-parametric dwarf-to-giant ratio (DGR) and the blue galaxy fraction (fb) to investigate the clustercentr
We review theoretical approaches to the study of galaxy formation, with emphasis on the role of hydrodynamic simulations in modeling the high redshift galaxy population. We present new predictions for the abundance of star-forming galaxies in the Lam