Please use this identifier to cite or link to this item:
http://hdl.handle.net/20.500.12386/31689
Title: | Towards cosmological constraints from the compressed modal bispectrum: A robust comparison of real-space bispectrum estimators | Authors: | Byun, Joyce Oddo, Andrea PORCIANI, CRISTIANO SEFUSATTI, Emiliano |
Issue Date: | 2021 | Journal: | JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS | Number: | 2021 | Issue: | 3 | First Page: | 105 | Abstract: | Higher-order clustering statistics, like the galaxy bispectrum, can add complementary cosmological information to what is accessible with two-point statistics, like the power spectrum. While the standard way of measuring the bispectrum involves estimating a bispectrum value in a large number of Fourier triangle bins, the compressed modal bispectrum approximates the bispectrum as a linear combination of basis functions and estimates the expansion coefficients on the chosen basis. In this work, we compare the two estimators by using parallel pipelines to analyze the real-space halo bispectrum measured in a suite of N-body simulations corresponding to a total volume of ∼ 1,000 h -3 Gpc3, with covariance matrices estimated from 10,000 mock halo catalogs. We find that the modal bispectrum yields constraints that are consistent and competitive with the standard bispectrum analysis: for the halo bias and shot noise parameters within the tree-level halo bispectrum model up to k max ≈ 0.06 (0.10) h Mpc-1, only 6 (10) modal expansion coefficients are necessary to obtain constraints equivalent to the standard bispectrum estimator using ∼ 20 to 1,600 triangle bins, depending on the bin width. For this work, we have implemented a modal estimator pipeline using Markov Chain Monte Carlo simulations for the first time, and we discuss in detail how the parameter posteriors and modal expansion are robust to, or sensitive to, several user settings within the modal bispectrum pipeline. The combination of the highly efficient compression that is achieved and the large number of mock catalogs available allows us to quantify how our modal bispectrum constraints depend on the number of mocks that are used to estimate covariance matrices and the functional form of the likelihood. | URI: | http://hdl.handle.net/20.500.12386/31689 | URL: | https://api.elsevier.com/content/abstract/scopus_id/85103611591 https://iopscience.iop.org/article/10.1088/1475-7516/2021/03/105 |
ISSN: | 1475-7516 | DOI: | 10.1088/1475-7516/2021/03/105 | Bibcode ADS: | 2021JCAP...03..105B | Fulltext: | open |
Appears in Collections: | 1.01 Articoli in rivista |
Files in This Item:
File | Description | Size | Format | |
---|---|---|---|---|
2010.09579.pdf | preprint | 8.37 MB | Adobe PDF | View/Open |
Byun_2021_JCAP.pdf | [Administrators only] | 8.59 MB | Adobe PDF |
Page view(s)
27
checked on Apr 19, 2024
Download(s)
22
checked on Apr 19, 2024
Google ScholarTM
Check
Altmetric
Altmetric
Items in DSpace are published in Open Access, unless otherwise indicated.