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Title: Galaxy Bias from the DES Science Verification Data: Combining Galaxy Density Maps and Weak Lensing Maps

We measure the redshift evolution of galaxy bias from a magnitude-limited galaxy sample by combining the galaxy density maps and weak lensing shear maps for a $$\sim$$116 deg$$^{2}$$ area of the Dark Energy Survey (DES) Science Verification data. This method was first developed in Amara et al. (2012) and later re-examined in a companion paper (Pujol et al., in prep) with rigorous simulation tests and analytical treatment of tomographic measurements. In this work we apply this method to the DES SV data and measure the galaxy bias for a magnitude-limited galaxy sample. We find the galaxy bias and 1$$\sigma$$ error bars in 4 photometric redshift bins to be 1.33$$\pm$$0.18 (z=0.2-0.4), 1.19$$\pm$$0.23 (z=0.4-0.6), 0.99$$\pm$$0.36 ( z=0.6-0.8), and 1.66$$\pm$$0.56 (z=0.8-1.0). These measurements are consistent at the 1-2$$\sigma$$ level with mea- surements on the same dataset using galaxy clustering and cross-correlation of galaxies with CMB lensing. In addition, our method provides the only $$\sigma_8$$-independent constraint among the three. We forward-model the main observational effects using mock galaxy catalogs by including shape noise, photo-z errors and masking effects. We show that our bias measurement from the data is consistent with that expected from simulations. With the forthcoming full DES data set, we expect this method to provide additional constraints on the galaxy bias measurement from more traditional methods. Furthermore, in the process of our measurement, we build up a 3D mass map that allows further exploration of the dark matter distribution and its relation to galaxy evolution.
Publication Date:
OSTI Identifier:
Report Number(s):
arXiv:1601.00405; FERMILAB-PUB-16-010-AE
DOE Contract Number:
Resource Type:
Journal Article
Resource Relation:
Journal Name: Mon.Not.Roy.Astron.Soc.
Research Org:
Argonne National Laboratory (ANL), Argonne, IL (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Brookhaven National Laboratory (BNL), Upton, NY (United States); SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States); Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States)
Sponsoring Org:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Contributing Orgs:
Country of Publication:
United States