The Spitzer-South Pole Telescope Survey: Linking galaxies and haloes at z=1.5
Abstract
We present results from the clustering of high redshift galaxies in the recently completed 94 deg2 Spitzer-SPT Deep Field survey. Applying flux and color cuts on the mid-infrared bands allows us to efficiently select galaxies at 1.5 in the stellar mass range 1010-1011 M⊙, making this the largest survey used so far to study such distant population. We fit halo occupation distributions to our clustering data and determine the explicit dependence on the halo mass of the central galaxy's stellar mass and the satellite occupation. We measure a prominent peak in the stellar to halo mass ratio at a halo mass of logMpeak = 12.4±0.08, which is 4x higher than low redshift values and supports an evolving mass threshold above which star formation is quenched. We find values of the large scale bias in the range bg=2-4 and satellite fractions fsat > 0.2, showing a clear and expected evolution compared to z=0 results. 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 such fraction increases slightly with the stellar mass limit at z=1.5, which is the opposite behavior than what is found at low redshift.
- Publication:
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American Astronomical Society Meeting Abstracts #223
- Pub Date:
- January 2014
- Bibcode:
- 2014AAS...22323105M