Dark Quest. I. Fast and Accurate Emulation of Halo Clustering Statistics and Its Application to Galaxy Clustering
Nov 23, 201846 pages
Published in:
- Astrophys.J. 884 (2019) 29
e-Print:
- 1811.09504 [astro-ph.CO]
DOI:
- 10.3847/1538-4357/ab3719 (publication)
Report number:
- YITP-19-73
View in:
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Abstract: (arXiv)
We perform an ensemble of -body simulations with particles for 101 flat CDM cosmological models sampled based on a maximin-distance Sliced Latin Hypercube Design. By using the halo catalogs extracted at multiple redshifts in the range of , we develop Dark Emulator, which enables fast and accurate computations of the halo mass function, halo-matter cross-correlation, and halo auto-correlation as a function of halo masses, redshift, separations and cosmological models, based on the Principal Component Analysis and the Gaussian Process Regression for the large-dimensional input and output data vector. We assess the performance of the emulator using a validation set of -body simulations that are not used in training the emulator. We show that, for typical halos hosting CMASS galaxies in the Sloan Digital Sky Survey, the emulator predicts the halo-matter cross correlation, relevant for galaxy-galaxy weak lensing, with an accuracy better than and the halo auto-correlation, relevant for galaxy clustering correlation, with an accuracy better than . We give several demonstrations of the emulator. It can be used to study properties of halo mass density profiles such as the mass-concentration relation and splashback radius for different cosmologies. The emulator outputs can be combined with an analytical prescription of halo-galaxy connection such as the halo occupation distribution at the equation level, instead of using the mock catalogs, to make accurate predictions of galaxy clustering statistics such as the galaxy-galaxy weak lensing and the projected correlation function for any model within the CDM cosmologies, in a few CPU seconds.Note:
- 46 pages, 47 figures; version accepted for publication in ApJ
References(138)
Figures(58)