Using 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 ~1% precision at the scales of interest, 0.1h-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, ƒ, and its degenerate combination, ƒσ8. 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 ƒσ8 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 ƒ and σ8, yielding an 11% constraint on ƒ alone for a BOSSlike 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
Zhai, Zhongxu, et al. "The Aemulus Project. III. Emulation of the Galaxy Correlation Function." The Astrophysical Journal, vol. 874, no. 1, Mar. 2019. https://doi.org/10.3847/1538-4357/ab0d7b
Zhai, Zhongxu, Tinker, Jeremy L., Becker, Matthew R., DeRose, Joseph, Mao, Yao-Yuan, McClintock, T., McLaughlin, Sean, Rozo, E., & Wechsler, Risa H. (2019). The Aemulus Project. III. Emulation of the Galaxy Correlation Function. The Astrophysical Journal, 874(1). https://doi.org/10.3847/1538-4357/ab0d7b
Zhai, Zhongxu, Tinker, Jeremy L., Becker, Matthew R., et al., "The Aemulus Project. III. Emulation of the Galaxy Correlation Function," The Astrophysical Journal 874, no. 1 (2019), https://doi.org/10.3847/1538-4357/ab0d7b
@article{osti_1571279,
author = {Zhai, Zhongxu and Tinker, Jeremy L. and Becker, Matthew R. and DeRose, Joseph and Mao, Yao-Yuan and McClintock, T. and McLaughlin, Sean and Rozo, E. and Wechsler, Risa H.},
title = {The Aemulus Project. III. Emulation of the Galaxy Correlation Function},
annote = {Using 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 ~1% precision at the scales of interest, 0.1h-1 Mpc r 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, ƒ, and its degenerate combination, ƒσ8. 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 ƒσ8 from r 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 ƒ and σ8, yielding an 11% constraint on ƒ alone for a BOSSlike 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},
doi = {10.3847/1538-4357/ab0d7b},
url = {https://www.osti.gov/biblio/1571279},
journal = {The Astrophysical Journal},
issn = {ISSN 0004-637X},
number = {1},
volume = {874},
place = {United States},
publisher = {Institute of Physics (IOP)},
year = {2019},
month = {03}}