Constraining galaxy–halo connection with high-order statistics

• Published in: Monthly notices of the Royal Astronomical Society Vol. 515; no. 4; pp. 6133 - 6150
• Main Authors: Zhang, Hanyu, Samushia, Lado, Brooks, David, de la Macorra, Axel, Doel, Peter, Gaztañaga, Enrique, Gontcho A Gontcho, Satya, Honscheid, Klaus, Kehoe, Robert, Kisner, Theodore, Meisner, Aaron, Poppett, Claire, Schubnell, Michael, Tarle, Gregory, Zhang, Kai, Zou, Hu
• Format: Journal Article
• Language: English
• Published: United Kingdom Oxford University Press 23.08.2022
• Subjects: ASTRONOMY AND ASTROPHYSICS; cosmology; galaxies; haloes; large-scale structure of the universe; simulations; software; theory; large-scale structure of Universe; cosmology: theory; galaxies: haloes
• ISSN: 0035-8711; 1365-2966
• DOI: 10.1093/mnras/stac2147

ABSTRACT We investigate using three-point statistics in constraining the galaxy–halo connection. We show that for some galaxy samples, the constraints on the halo occupation distribution parameters are dominated by the three-point function signal (over its two-point counterpart). We demonstrate this on mock catalogues corresponding to the Luminous red galaxies (LRGs), Emission-line galaxies (ELGs), and quasars (QSOs) targeted by the Dark Energy Spectroscopic Instrument (DESI) Survey. The projected three-point function for triangle sides less up to 20 h−1 Mpc measured from a cubic Gpc of data can constrain the characteristic minimum mass of the LRGs with a preci sion of 0.46 per cent. For comparison, similar constraints from the projected two-point function are 1.55 per cent. The improvements for the ELGs and QSOs targets are more modest. In the case of the QSOs, it is caused by the high shot-noise of the sample, and in the case of the ELGs, it is caused by the range of halo masses of the host haloes. The most time-consuming part of our pipeline is the measurement of the three-point functions. We adopt a tabulation method, proposed in earlier works for the two-point function, to significantly reduce the required compute time for the three-point analysis.