TY - JOUR
T1 - The Spitzer South Pole Telescope Deep-Field Survey
T2 - Linking galaxies and haloes at z = 1.5
AU - Martinez-Manso, Jesus
AU - Gonzalez, Anthony H.
AU - Ashby, Matthew L.N.
AU - Stanford, S. A.
AU - Brodwin, Mark
AU - Holder, Gilbert P.
AU - Stern, Daniel
N1 - Publisher Copyright:
© 2014 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.
PY - 2015/1/1
Y1 - 2015/1/1
N2 - We present an analysis of the clustering of high-redshift galaxies in the recently completed 94 deg2 Spitzer South Pole Telescope Deep-Field survey. Applying flux and colour cuts to the mid-infrared photometry efficiently selects galaxies at z ~ 1.5 in the stellar mass range 1010-1011 M⊙, making this sample the largest used so far to study such a distant population. We measure the angular correlation function in different flux-limited samples at scales >6 arcsec (corresponding to physical distances >0.05 Mpc) and thereby map the one- and two-halo contributions to the clustering. We fit halo occupation distributions and determine how the central galaxy's stellar mass and satellite occupation depend on the halo mass. We measure a prominent peak in the stellar-to-halo mass ratio at a halo mass of log (Mhalo/M⊙) = 12.44 ± 0.08, 4.5 times higher than the z = 0 value. This supports the idea of an evolving mass threshold above which star formation is quenched. We estimate the large-scale bias in the range bg = 2-4 and the satellite fraction to be fsat ~ 0.2, showing a clear evolution compared to z = 0. We also find that, above a given stellar mass limit, the fraction of galaxies that are in similar mass pairs is higher at z = 1.5 than at z = 0. In addition, we measure that this fraction mildly increases with the stellar mass limit at z = 1.5, which is the opposite of the behaviour seen at low redshift.
AB - We present an analysis of the clustering of high-redshift galaxies in the recently completed 94 deg2 Spitzer South Pole Telescope Deep-Field survey. Applying flux and colour cuts to the mid-infrared photometry efficiently selects galaxies at z ~ 1.5 in the stellar mass range 1010-1011 M⊙, making this sample the largest used so far to study such a distant population. We measure the angular correlation function in different flux-limited samples at scales >6 arcsec (corresponding to physical distances >0.05 Mpc) and thereby map the one- and two-halo contributions to the clustering. We fit halo occupation distributions and determine how the central galaxy's stellar mass and satellite occupation depend on the halo mass. We measure a prominent peak in the stellar-to-halo mass ratio at a halo mass of log (Mhalo/M⊙) = 12.44 ± 0.08, 4.5 times higher than the z = 0 value. This supports the idea of an evolving mass threshold above which star formation is quenched. We estimate the large-scale bias in the range bg = 2-4 and the satellite fraction to be fsat ~ 0.2, showing a clear evolution compared to z = 0. We also find that, above a given stellar mass limit, the fraction of galaxies that are in similar mass pairs is higher at z = 1.5 than at z = 0. In addition, we measure that this fraction mildly increases with the stellar mass limit at z = 1.5, which is the opposite of the behaviour seen at low redshift.
KW - Cosmology: observations
KW - Galaxies: evolution
KW - Galaxies: haloes
KW - Galaxies: high-redshift
KW - Large-scale structure of Universe
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U2 - 10.1093/mnras/stu1998
DO - 10.1093/mnras/stu1998
M3 - Article
AN - SCOPUS:84924429659
SN - 0035-8711
VL - 446
SP - 169
EP - 194
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
IS - 1
ER -