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Stellar Masses of High-Redshift Galaxies

Casey Papovich·Mark Dickinson·Harry Ferguson
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Abstract

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.

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Casey Papovich, Mark Dickinson, Harry Ferguson. 2002-01-14. Stellar Masses of High-Redshift Galaxies. https://doi.org/10.1007/10899892_73

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