TY - JOUR

T1 - Evolution of the galaxy stellar mass function

T2 - evidence for an increasing M* from z=2 to the present day

AU - Adams, N. J.

AU - Bowler, R. A. A.

AU - Jarvis, M. J.

AU - Haeussler, B.

AU - Lagos, C. D. P.

PY - 2021/10/4

Y1 - 2021/10/4

N2 - Utilizing optical and near-infrared broad-band photometry covering >5deg(2) in two of the most well-studied extragalactic legacy fields (COSMOS and XMM-LSS), we measure the galaxy stellar mass function (GSMF) between 0.1 < z < 2.0. We explore in detail the effect of two source extraction methods (SExtractor and ProFound) in addition to the inclusion/exclusion of Spitzer IRAC 3.6 and 4.5 mu m photometry when measuring the GSMF. We find that including IRAC data reduces the number of massive (log(10)(M/M-circle dot) > 11.25) galaxies found due to improved photometric redshift accuracy, but has little effect on the more numerous lower-mass galaxies. We fit the resultant GSMFs with double Schechter functions down to log(10)(M/M-circle dot) = 7.75 (9.75) at z = 0.1 (2.0) and find that the choice of source extraction software has no significant effect on the derived best-fitting parameters. However, the choice of methodology used to correct for the Eddington bias has a larger impact on the high-mass end of the GSMF, which can partly explain the spread in derived M* values from previous studies. Using an empirical correction to model the intrinsic GSMF, we find evidence for an evolving characteristic stellar mass with delta log(10)(M*/M-circle dot)/delta z = , when using SExtractor (ProFound). We argue that with widely quenched star formation rates in massive galaxies at low redshift (z < 0.5), additional growth via mergers is required in order to sustain such an evolution to a higher characteristic mass.

AB - Utilizing optical and near-infrared broad-band photometry covering >5deg(2) in two of the most well-studied extragalactic legacy fields (COSMOS and XMM-LSS), we measure the galaxy stellar mass function (GSMF) between 0.1 < z < 2.0. We explore in detail the effect of two source extraction methods (SExtractor and ProFound) in addition to the inclusion/exclusion of Spitzer IRAC 3.6 and 4.5 mu m photometry when measuring the GSMF. We find that including IRAC data reduces the number of massive (log(10)(M/M-circle dot) > 11.25) galaxies found due to improved photometric redshift accuracy, but has little effect on the more numerous lower-mass galaxies. We fit the resultant GSMFs with double Schechter functions down to log(10)(M/M-circle dot) = 7.75 (9.75) at z = 0.1 (2.0) and find that the choice of source extraction software has no significant effect on the derived best-fitting parameters. However, the choice of methodology used to correct for the Eddington bias has a larger impact on the high-mass end of the GSMF, which can partly explain the spread in derived M* values from previous studies. Using an empirical correction to model the intrinsic GSMF, we find evidence for an evolving characteristic stellar mass with delta log(10)(M*/M-circle dot)/delta z = , when using SExtractor (ProFound). We argue that with widely quenched star formation rates in massive galaxies at low redshift (z < 0.5), additional growth via mergers is required in order to sustain such an evolution to a higher characteristic mass.

KW - galaxies: abundances

KW - galaxies: evolution

KW - galaxies: general

KW - ACTIVE GALACTIC NUCLEI

KW - LYMAN-BREAK GALAXIES

KW - SPECTRAL ENERGY-DISTRIBUTIONS

KW - STAR-FORMATION RATES

KW - LUMINOSITY FUNCTION

KW - BLACK-HOLES

KW - ASSEMBLY GAMA

KW - PHOTOMETRIC REDSHIFTS

KW - SOURCE EXTRACTION

KW - COSMIC EVOLUTION

U2 - 10.1093/mnras/stab1956

DO - 10.1093/mnras/stab1956

M3 - Journal article

VL - 506

SP - 4933

EP - 4951

JO - Royal Astronomical Society. Monthly Notices

JF - Royal Astronomical Society. Monthly Notices

SN - 0035-8711

IS - 4

ER -