PRIMUS: Constraints on Star Formation Quenching and Galaxy Merging, and the Evolution of the Stellar Mass Function from z = 0-1

摘要: We measure the evolution of stellar mass function (SMF) from z = 0−1 using multi-wavelength imaging and spectroscopic redshifts PRism MUlti-object Survey (PRIMUS) Sloan Digital Sky (SDSS). From PRIMUS we construct an i < 23 flux-limited sample ∼ 40,000 galaxies at 0.2 − 1.0 over five fields totaling ≈ 5.5 deg 2 , SDSS select 170,000 atz 0.01−0.2 that analyze consistently with respect to minimize systematic errors in our evolutionary measurements. find SMF all evolves relatively little since 1, although do evidence for assembly downsizing; a 30% increase number density 10 M⊙ sincez 0.6, . 10% change & 11 1. Dividing into star-forming quiescent evolving cut specific star-formation rate, stays constant whereas space-density decreases by 50% between 1 0. Meanwhile, increases steeply towards low redshift, factor 3 while massive remains approximately These results suggest rate which are quenched decreasing mass, but bulk buildup within population occurs around 10.8 M⊙. In addition, conclude mergers not appear be dominant channel even among (& M⊙) galaxies. Subject headings: Surveys – galaxies: high-redshift cosmology: large-scale structure universe