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We present constraints on the stellar-mass distribution of distant galaxies. These stellar-mass estimates derive from fitting population-synthesis models to the galaxies observed multi-band spectrophotometry. We discuss the complex uncertainties (both statistical and systematic) that are inherent to this method, and offer future prospects to improve the constraints. Typical uncertainties for galaxies at z ~ 2.5 are ~ 0.3 dex (statistical), and factors of ~ 3 (systematic). By applying this method to a catalog of NICMOS-selected galaxies in the Hubble Deep Field North, we generally find a lack of high-redshift galaxies (z > 2) with masses comparable to those of present-day ``L* galaxies. At z < 1.8, galaxies with L*-sized masses do emerge, but with a number density below that at the present epoch. Thus, it seems massive, present-day galaxies were not fully assembled by z ~ 2.5, and that further star formation and/or merging are required to assemble them from these high-redshift progenitors. Future progress on this subject will greatly benefit from upcoming surveys such as those planned with HST/ACS and SIRTF.
Using the VLT we have obtained high quality spectra of about 70 high redshift (1- 4.6) galaxies within the FORS Deep Field (FDF). As expected most of them turn out to be (bright) starburst galaxies and the observed spectra agree with synthetic ones.
We use high-resolution ($approx 10$ pc), zoom-in simulations of a typical (stellar mass $M_starsimeq10^{10}M_odot$) Lyman Break Galaxy (LBG) at $zsimeq 6$ to investigate the stellar populations of its six dwarf galaxy satellites, whose stellar [gas]
We present a combined analysis of rest-frame far-UV (1000-2000 A) and rest-frame optical (3600-7000 A) composite spectra formed from very deep observations of a sample of 30 star-forming galaxies with z=2.4+/-0.1, selected to be representative of the
Recent observations have shown that the characteristic luminosity of the rest-frame ultraviolet (UV) luminosity function does not significantly evolve at 4 < z < 7 and is approximately M*_UV ~ -21. We investigate this apparent non-evolution by examin
Recent observations have gathered a considerable sample of high redshift galaxy candidates and determined the evolution of their luminosity function (LF). To interpret these findings, we use cosmological SPH simulations including, in addition to stan