English
Related papers

Related papers: Efficiently emulating distribution functions in gi…

200 papers

We test different implementations of the halo occupation distribution (HOD) model to reconstruct the spatial distribution of galaxies as predicted by a publicly available semi-analytical model (SAM). We compare the measured two-point…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-16 Esteban Jiménez , Sergio Contreras , Nelson Padilla , Idit Zehavi , Carlton M. Baugh , Violeta Gonzalez-Perez

We propose a new numerical procedure to simulate a single dark halo of any size and mass in a hierarchical framework coupling the extended Press-Schechter formalism (EPSF) to N-body simulations. The procedure consists of assigning…

Astrophysics · Physics 2009-11-07 Elena D'Onghia , Claudio Firmani , Guido Chincarini

The simple, conventional dark matter halo mass definitions commonly used in cosmological simulations ("virial" mass, FoF mass, $M_{50,100,200,...}$) only capture part of the collapsed material and are therefore inconsistent with the halo…

Cosmology and Nongalactic Astrophysics · Physics 2011-11-14 Donnino Anderhalden , Juerg Diemand

The friends-of-friends algorithm (hereafter, FOF) is a percolation algorithm which is routinely used to identify dark matter halos from N-body simulations. We use results from percolation theory to show that the boundary of FOF halos does…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Surhud More , Andrey Kravtsov , Neal Dalal , Stefan Gottlöber

We examine the efficacy of the halo mass function as a probe of $f(R)$, symmetron and DGP gravity. We develop an excursion-set method to generalise a range of popular HMF fitting functions from GR to screened MG, considering the HMF…

Cosmology and Nongalactic Astrophysics · Physics 2018-12-26 Francesca von Braun-Bates , Julien Devriendt

In this work, we expand and test the capabilities of our recently developed super-resolution (SR) model to generate high-resolution (HR) realizations of the full phase-space matter distribution, including both displacement and velocity,…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-20 Yueying Ni , Yin Li , Patrick Lachance , Rupert A. C. Croft , Tiziana Di Matteo , Simeon Bird , Yu Feng

We propose a method to generate `genetically-modified' (GM) initial conditions for high-resolution simulations of galaxy formation in a cosmological context. Building on the Hoffman-Ribak algorithm, we start from a reference simulation with…

Astrophysics of Galaxies · Physics 2016-01-29 Nina Roth , Andrew Pontzen , Hiranya V. Peiris

We use cosmological hydrodynamic simulations to consistently compare the assembly of dwarf galaxies in both $\Lambda$ dominated, Cold (CDM) and Self--Interacting (SIDM) dark matter models. The SIDM model adopts a constant cross section of 2…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-28 A. Bastidas Fry , F. Governato , A. Pontzen , T. Quinn , M. Tremmel , L. Anderson , H. Menon , A. M. Brooks , J. Wadsley

We revisit the derivation of the mass function and the bias of dark matter halos for non-Gaussian initial conditions. We use a steepest-descent approach to point out that exact results can be obtained for the high-mass tail of the halo mass…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 P. Valageas

We investigate how different cosmological parameters, such as those delivered by the WMAP and Planck missions, affect the nature and evolution of dark matter halo substructure. We use a series of flat $\Lambda$ cold dark matter…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 Gregory A. Dooley , Brendan F. Griffen , Phillip Zukin , Alexander P. Ji , Mark Vogelsberger , Lars E. Hernquist , Anna Frebel

For many analyses in cosmology it is necessary to reconstruct the likely distribution of unobserved fields, such as dark matter or non-luminous baryons, from observed luminous tracers. The dominant approach in cosmology has been to use the…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-16 Jordan Krywonos , Yurii Kvasiuk , Matthew C. Johnson , Moritz Münchmeyer

AI super-resolution, combining deep learning and N-body simulations has been shown to successfully reproduce the large scale structure and halo abundances in the Lambda Cold Dark Matter cosmological model. Here, we extend its use to models…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-16 Meris Sipp , Patrick LaChance , Rupert Croft , Yueying Ni , Tiziana Di Matteo

I calculate the mass function evolution in a $\Lambda$CDM model by means of the excursion set model and an improved version of the barrier shape obtained in Del Popolo & Gambera (1998), which implicitly takes account of the total angular…

Astrophysics · Physics 2008-11-26 A. Del Popolo

Approximate N-body methods, such as FastPM and COLA, have been successful in modelling halo and galaxy clustering statistics, but their low resolution on small scales is a limitation for applications that require high precision. Full N-body…

Instrumentation and Methods for Astrophysics · Physics 2024-06-18 Yiheng Wu , Hong Guo , Volker Springel

Building upon results of cosmological simulations of ultra-light scalar field dark matter (SFDM), we present a comprehensive model for the density profiles of SFDM haloes as a function of halo virial mass $M_{\rm h}$ and scalar field mass…

Cosmology and Nongalactic Astrophysics · Physics 2018-12-12 Victor H. Robles , James S. Bullock , Michael Boylan-Kolchin

For the first time, we develop a simulation-based model for the Minkowski functionals (MFs) of large-scale structure, which allows us to extract the full information available from the MFs (including both the Gaussian and non-Gaussian…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-20 Wei Liu , Enrique Paillas , Carolina Cuesta-Lazaro , Georgios Valogiannis , Wenjuan Fang

Cosmological emulators of observables such as the Cosmic Microwave Background (CMB) spectra and matter power spectra commonly use training data sampled from a Latin hypercube. This method often incurs high computational costs by covering…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-03 Andreas Nygaard , Emil Brinch Holm , Steen Hannestad , Thomas Tram

Modern cosmological inference increasingly relies on differentiable models to enable efficient, gradient-based parameter estimation and uncertainty quantification. Here, we present a novel approach for predicting the abundance of dark…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-08 Jim Buisman , Florian List , Oliver Hahn

The claimed detection of large amounts of substructure in lensing flux anomalies, and in Milky Way stellar stream gaps statistics, has lead to a step change in constraints on simple warm dark matter models. In this study we compute…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-20 M. R. Lovell

Numerical simulations show that redshift space distortions (RSD) introduce strong scale dependence in the power spectra of halos, with ten percent deviations relative to linear theory predictions even on relatively large scales (k<0.1h/Mpc)…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Zvonimir Vlah , Uroš Seljak , Teppei Okumura , Vincent Desjacques
‹ Prev 1 8 9 10 Next ›