1412.7162
PRIMUS: galaxy environment on the quiescent fraction evolution at z<0.8
Hahn, et al
Investigate the effects of galaxy environment on the evolution of the quiescent fraction ($f_\mathrm{Q}$) from z=0.8 to 0.0 using spectroscopic redshifts and multi-wavelength imaging data from the PRIsm Multi-Object Survey (PRIMUS) and the SDSS. The stellar mass limited galaxy sample consists of ~14k PRIMUS galaxies within 0.2<z<0.8 and ~64k SDSS galaxies of 0.05<z<0.12. Classify the galaxies as quiescent or star-forming based on an evolving specific SF 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 SF galaxies in low or high density environments, examine the evolution of their SMF. Then using the SMFs, compute $f_Q(M*)$ and quantify its evolution within the redshift range. 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 1e10.5 Msun, for 0.1<z<0.7, the quiescent fraction rises by 15% at the lowest environments and by 25% at the highest environments measured. These results suggest that for a minority of galaxies their cessation of SF 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.
1412.7521
A measurement of gravitational lensing of the cosmic microwave background by galaxy clusters using data from the South Pole Telescope
Baxter, et al
Stat error ~ sys error, so attempt no correction. 513 clusters selected via their SZ signatures in SPT data. Rule out null hypothesis of no lensing at 3.0 sigma. The lensing-derived mass estimate fro the full cluster sample is consistent with that inferred from the SZ flux: M200,lens = 0.76pm0.36 M200,SZ (68% CL, stat error only).
PRIMUS: galaxy environment on the quiescent fraction evolution at z<0.8
Hahn, et al
Investigate the effects of galaxy environment on the evolution of the quiescent fraction ($f_\mathrm{Q}$) from z=0.8 to 0.0 using spectroscopic redshifts and multi-wavelength imaging data from the PRIsm Multi-Object Survey (PRIMUS) and the SDSS. The stellar mass limited galaxy sample consists of ~14k PRIMUS galaxies within 0.2<z<0.8 and ~64k SDSS galaxies of 0.05<z<0.12. Classify the galaxies as quiescent or star-forming based on an evolving specific SF 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 SF galaxies in low or high density environments, examine the evolution of their SMF. Then using the SMFs, compute $f_Q(M*)$ and quantify its evolution within the redshift range. 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 1e10.5 Msun, for 0.1<z<0.7, the quiescent fraction rises by 15% at the lowest environments and by 25% at the highest environments measured. These results suggest that for a minority of galaxies their cessation of SF 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.
1412.7521
A measurement of gravitational lensing of the cosmic microwave background by galaxy clusters using data from the South Pole Telescope
Baxter, et al
Stat error ~ sys error, so attempt no correction. 513 clusters selected via their SZ signatures in SPT data. Rule out null hypothesis of no lensing at 3.0 sigma. The lensing-derived mass estimate fro the full cluster sample is consistent with that inferred from the SZ flux: M200,lens = 0.76pm0.36 M200,SZ (68% CL, stat error only).
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