The Aemulus Project. III. Emulation of the Galaxy Correlation Function
Tinker, Jeremy L.
Becker, Matthew R.
Wechsler, Risa H.
AffiliationUniv Arizona, Dept Phys
MetadataShow full item record
PublisherIOP PUBLISHING LTD
CitationZhongxu Zhai et al 2019 ApJ 874 95
Rights© 2019. The American Astronomical Society. All rights reserved.
Collection InformationThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at email@example.com.
AbstractUsing the N-body simulations of the AEMULUS Project, we construct an emulator for the nonlinear clustering of galaxies in real and redshift space. We construct our model of galaxy bias using the halo occupation framework, accounting for possible velocity bias. The model includes 15 parameters, including both cosmological and galaxy bias parameters. We demonstrate that our emulator achieves similar to 1% precision at the scales of interest, 0.1 h(-1) Mpc < r < 10 h(-1) Mpc, and recovers the true cosmology when tested against independent simulations. Our primary parameters of interest are related to the growth rate of structure, f, and its degenerate combination, f sigma(8). Using this emulator, we show that the constraining power on these parameters monotonically increases as smaller scales are included in the analysis, all the way down to 0.1 h(-1) Mpc. For a BOSS-like survey, the constraints on f sigma(8) from r < 30 h(-1) Mpc scales alone are nearly a factor of two tighter than those from the fiducial BOSS analysis of redshift-space clustering using perturbation theory at larger scales. The combination of real- and redshift-space clustering allows us to break the degeneracy between f and sigma(8), yielding an 11% constraint on f alone for a BOSS-like analysis. The current AEMULUS simulations limit this model to surveys of massive galaxies. Future simulations will allow this framework to be extended to all galaxy target types, including emission-line galaxies.
VersionFinal published version
SponsorsU.S. Department of Energy [DE-AC02-76SF00515]; NSF [AST-1211889]; Samuel P. Langley PITT PACC Postdoctoral Fellowship; Office of Science of the U.S. Department of Energy [DE-AC02-05CH11231]