ChangHoon Hahn

PRIMUS: Effects of Galaxy Environment on the Quiescent Fraction Evolution at z < 0.8

We investigate the effects of galaxy environment on the evolution of the quiescent fraction (

Halo histories versus galaxy properties at z = 0 II: Large-scale galactic conformity

f_\mathrm{Q}

Clustering of quasars in the First Year of the SDSS-IV eBOSS survey: Interpretation and halo occupation distribution

) from z =0.8 to 0.0 using spectroscopic redshifts and multi-wavelength imaging data from the PRIsm MUlti-object Survey (PRIMUS) and the Sloan Digitial Sky Survey (SDSS). Our stellar mass limited galaxy sample consists of ~14,000 PRIMUS galaxies within z = 0.2-0.8 and ~64,000 SDSS galaxies within z = 0.05-0.12. We classify the galaxies as quiescent or star-forming based on an evolving specific star formation cut, and as low or high density environments based on fixed cylindrical aperture environment measurements on a volume-limited environment defining population. For quiescent and star-forming galaxies in low or high density environments, we examine the evolution of their stellar mass function (SMF). Then using the SMFs we compute

The Effect of Fiber Collisions on the Galaxy Power Spectrum Multipoles

f_\mathrm{Q}(M_{*})

The clustering of luminous red galaxies at z ∼ 0.7 from EBOSS and BOSS data

and quantify its evolution within our redshift range. We find that the quiescent fraction is higher at higher masses and in denser environments. The quiescent fraction rises with cosmic time for all masses and environments. At a fiducial mass of

Accurate halo–galaxy mocks from automatic bias estimation and particle mesh gravity solvers

10^{10.5}M_\odot

Halo histories versus galaxy properties at z = 0 – III. The properties of star-forming galaxies

, from z~0.7 to 0.1, the quiescent fraction rises by 15% at the lowest environments and by 25% at the highest environments we measure. These results suggest that for a minority of galaxies their cessation of star formation is due to external influences on them. However, in the recent Universe a substantial fraction of the galaxies that cease forming stars do so due to internal processes.

Approximate Bayesian computation in large-scale structure: constraining the galaxy–halo connection

Author(s): Tinker, JL; Hahn, CH; Mao, YY; Wetzel, AR; Conroy, C | Abstract:

Star Formation Quenching Timescale of Central Galaxies in a Hierarchical Universe

SRT is grateful for support from the Campus de Excelencia Internacional UAM/CSIC. SRT, JC, FP acknowledge support from the Spanish MICINN Consolider-Ingenio 2010 Programme under grant MultiDark CSD2009-00064 MINECO Severo Ochoa Award SEV-2012-0249 and grant AYA2014-60641-C2-1-P. GY acknowledges financial support from MINECO/FEDER (Spain) under research grants AYA2012-31101 and AYA201563810-P.

The clustering of luminous red galaxies at z

Fiber-fed multi-object spectroscopic surveys, with their ability to collect an unprecedented number of redshifts, currently dominate large-scale structure studies. However, physical constraints limit these surveys from successfully collecting redshifts from galaxies too close to each other on the focal plane. This ultimately leads to significant systematic effects on galaxy clustering measurements. Using simulated mock catalogs, we demonstrate that fiber collisions have a significant impact on the power spectrum,