2019/10/03 by ChangHoon Hahn, Jeremy L. Tinker, Hahn, ChangHoon +3
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysics of Galaxies (astro-ph.GA) #Cosmology and Nongalactic Astrophysics (astro-ph.CO) #FOS: Physical sciences #Galaxies: Formation, Evolution, Phenomena #Scientific Research and Discoveries
paper · pdf · doi:10.48550/arxiv.1910.01644
openalex publication_date 2019/10/03 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We present constraints on the timescale of star formation variability and the correlation between star formation and host halo accretion histories of star-forming (SF) central galaxies from the scatter of the stellar-to-halo mass relation (SHMR). SF galaxies are found to have a tight relationship between their star formation rates and stellar masses on the so-called "star-forming sequence" (SFS), which characterizes their SF histories and M_* growths. Meanwhile, observed SHMR constraints connect M_* growth to halo accretion history. Combining these observed trends with a cosmological N-body simulation, we present flexible models that track the SF, M_*, and halo accretion histories of SF central galaxies at z<1 while reproducing the observed stellar mass function and SFS in SDSS DR7. We find that the scatter in SHMR at Mh=1012M_\odot, σM_*|Mh=1012M_\odot, is sensitive to the timescale of star formation variability, t\rm duty, and the correlation coefficient, r, between SF and halo accretion histories: shorter t\rm duty and higher r both result in tighter σM_*|Mh=1012M_\odot. To reproduce a constant 0.2 dex scatter over z=1-0, our models require t\rm duty≤1.5 Gyr for r=0.99 or r>0.6 for t\rm duty=0.1 Gyr. For r∼0.6, as found in the literature, t\rm duty<0.2 Gyr is necessary. Meanwhile, to reproduce the tightening of σM_*|Mh=1012M_\odot=0.35 to 0.2 dex from z=1-0 in hydrodynamical simulations, our models require t\rm duty=0.1 Gyr for r>0.5. Although, the lack of consensus on σM_*|Mh=1012M_\odot at Mh=1012M_\odot and at z=1 from observations and galaxy formation models remains the main bottleneck in precisely constraining r and t\rm duty, we demonstrate that SHMR can be used to constrain the SF and host halo accretion histories of SF central galaxies.