{"about":{"site":"https://codewithpapers.app","non_affiliation":"Code with Papers and Syntology are not affiliated with, endorsed by, or sponsored by Papers with Code, Meta, or the pwc-archive mirror.","licence":"CC BY-SA 4.0","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","attribution":"https://codewithpapers.app/attribution","modified":"archive material modified by Syntology; see the attribution page"},"url":"/paper/the-e-mantis-emulator-fast-and-accurate","title":"The e-MANTIS emulator: fast and accurate predictions of the halo mass function in $f(R)$CDM and $w$CDM cosmologies","arxiv_id":"2410.05226","date":"2024-10-07","proceeding":null,"authors":["I. Sáez-Casares","Y. Rasera","T. R. G. Richardson","P. -S. Corasaniti"],"abstract":"In this work, we present a novel emulator of the halo mass function, which we implement in the framework of the e-mantis emulator of $f(R)$ gravity models. We also extend e-mantis to cover a larger cosmological parameter space and to include models of dark energy with a constant equation of state $w$CDM. We use a Latin hypercube sampling of the $w$CDM and $f(R)$CDM cosmological parameter spaces, over a wide range, and realize a large suite of more than $10000$ $N$-body simulations of different volume, mass resolution and random phase of the initial conditions. For each simulation in the suite, we generate halo catalogues using the friends-of-friends halo finder, as well as the spherical overdensity algorithm for different overdensity thresholds. We decompose the corresponding halo mass functions on a B-spline basis, and use this decomposition to train an emulator based on Gaussian processes. The resulting emulator is able to predict the halo mass function for redshifts $\\leq 1.5$ and for halo masses $M_h\\geq10^{13}\\,h^{-1}M_\\odot$. The typical HMF errors for SO haloes with $\\Delta=200\\mathrm{c}$ at $z=0$ in $w$CDM (respectively $f(R)$CDM) are of order of $\\epsilon_0\\simeq1.5\\%$ ($\\epsilon_0\\simeq4\\%$) up to a transition mass $M_t\\simeq2\\cdot10^{14}\\,h^{-1}M_\\odot$ ($M_t\\simeq6\\cdot10^{13}\\,h^{-1}M_\\odot$). For larger masses, the errors are dominated by shot-noise and scale as $\\epsilon_0\\cdot\\left(M_h/M_t\\right)^\\alpha$ with $\\alpha\\simeq0.9$ ($\\alpha\\simeq0.4$) up to $M_h \\sim 10^{15}\\,h^{-1}M_\\odot$. Independently of this general trend, the emulator is able to provide an estimation of its own error as a function of the cosmological parameters, halo mass, and redshift. The e-mantis emulator, which is publicly available, can be used to obtain fast and accurate predictions of the halo mass function in the $f(R)$CDM and $w$CDM non-standard cosmological models.","url_abs":"https://arxiv.org/abs/2410.05226v1","url_pdf":"https://arxiv.org/pdf/2410.05226v1.pdf","source":{"archive":"pwc-archive (Hugging Face), CC BY-SA 4.0","snapshot":"2025-07-28","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","row_kind":"links_only","authors_date_abstract":"arXiv metadata, CC0 1.0 (https://info.arxiv.org/help/license), from the Kaggle arXiv metadata snapshot of 2026-09-12"},"code_links":[{"paper_slug":"the-e-mantis-emulator-fast-and-accurate","repo_url":"https://gitlab.obspm.fr/e-mantis/e-mantis","is_official":1,"mentioned_in_paper":0,"mentioned_in_github":0,"framework":"none","reach":null}],"tasks":[],"methods":[],"datasets_introduced":[],"methods_introduced":[],"results":[],"syntology":{"syntology_url":null,"atlas_url":null,"mcp":null,"developers":"https://syntology.ai/developers"},"arxiv_metadata":null,"syntology_extracted_results":null}