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Related papers: A Variable-Slope Smooth-$k$ Filter for Modeling Ha…

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We propose a new filter, a smooth-$k$ space filter, to use in the Press-Schechter approach to model the dark matter halo mass function which overcomes shortcomings of other filters. We test this against the mass function measured in N-body…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-04 Matteo Leo , Carlton M. Baugh , Baojiu Li , Silvia Pascoli

We study halo mass functions with the Press-Schechter formalism for interacting dark matter models, where matter power spectra are damped due to dark acoustic oscillations in the early universe. After adopting a smooth window function, we…

Cosmology and Nongalactic Astrophysics · Physics 2019-04-18 Omid Sameie , Andrew J. Benson , Laura V. Sales , Hai-Bo Yu , Leonidas A. Moustakas , Peter Creasey

We study the halo mass function and inner halo structure at high redshifts ($z\geq5$) for a suite of simulations within the structure formation ETHOS framework. Scenarios such as cold dark matter (CDM), thermal warm dark matter (WDM), and…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-30 Sebastian Bohr , Jesús Zavala , Francis-Yan Cyr-Racine , Mark Vogelsberger

We analyse the effect of two relevant physical constraints on the mass multiplicity function of dark matter halos in a Press--Schechter type algorithm. Considering the random--walk of linear Gaussian density fluctuations as a function of…

Astrophysics · Physics 2015-06-24 C. Porciani , F. Ferrini , F. Lucchin , S. Matarrese

We propose a new alternative to the Weakly Interacting Massive Particle (WIMP) paradigm for dark matter. Rather than being determined by thermal freeze-out, the dark matter abundance in this scenario is set by dark matter decay, which is…

High Energy Physics - Phenomenology · Physics 2017-08-16 Michael J. Baker , Joachim Kopp

Well-motivated elementary particle candidates for the dark matter, such as the sterile neutrino, behave as warm dark matter (WDM).For particle masses of order a keV, free streaming produces a cutoff in the linear fluctuation power spectrum…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-20 Mark R. Lovell , Carlos S. Frenk , Vincent R. Eke , Adrian Jenkins , Liang Gao , Tom Theuns

A body of recent work has focused on constructing a variational family of filtered distributions using Sequential Monte Carlo (SMC). Inspired by this work, we introduce Particle Smoothing Variational Objectives (SVO), a novel backward…

Machine Learning · Statistics 2019-09-24 Antonio Khalil Moretti , Zizhao Wang , Luhuan Wu , Iddo Drori , Itsik Pe'er

We present a useful function for describing the profiles of dark-matter haloes with a varying asymptotic inner slope -\alpha, ranging from a cusp to a core, where the profiles of density, mass-velocity and potential are simple analytic…

Astrophysics of Galaxies · Physics 2016-10-06 Avishai Dekel , Guy Ishai , Aaron A. Dutton , Andrea V. Maccio

For around 100 years, hydrogen spectral modelling has been based on Voigt profile fitting. The semi-classical Voigt profile is based on a 2-level atom approximation. Whilst the Voigt profile is excellent for many circumstances, the accuracy…

General Relativity and Quantum Cosmology · Physics 2020-01-08 C. C. Lee , J. K. Webb , R. F. Carswell

Smoothed particle hydrodynamics (SPH) has been extensively studied in computer graphics to animate fluids with versatile effects. However, SPH still suffers from two numerical difficulties: the particle deficiency problem, which will…

Graphics · Computer Science 2020-01-29 Xiaowei He , Huamin Wang , Guoping Wang , Hongan Wang , Enhua Wu

Integral measures of weak gravitational lensing by dark-matter haloes, like the aperture mass, are sensitive to different physical halo properties dependent on the halo mass density profile. For isothermal profiles, the relation between…

Astrophysics · Physics 2009-11-06 Matthias Bartelmann , Lindsay King , Peter Schneider

The weakly compressible Smoothed Particle Hydrodynamics (SPH) is known to suffer from the pressure oscillation, which would undermine the simulation stability and accuracy. To address this issue, we propose a generalized density dissipation…

Fluid Dynamics · Physics 2023-08-30 Bo Xue Zheng , Zhi Wen Cai , Pei Dong Zhao , Xiao Yang Xu , Tak Shing Chan , Peng Yu

Accurate knowledge of the non-linear dark-matter power spectrum is important for understanding the large-scale structure of the Universe, the statistics of dark-matter haloes and their evolution, and cosmological gravitational lensing. We…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Carlo Giocoli , Matthias Bartelmann , Ravi K. Sheth , Marcello Cacciato

Thermal inflation models (which feature two inflationary stages) can display damped primordial curvature power spectra on small scales which generate damped matter fluctuations. For a reasonable choice of parameters, thermal inflation…

Cosmology and Nongalactic Astrophysics · Physics 2018-12-11 Matteo Leo , Carlton M. Baugh , Baojiu Li , Silvia Pascoli

Press-Schechter theory gives a simple, approximate functional form of the mass function of dark matter haloes. Sheth and Tormen (ST) refined this mass function to give an improved analytical fit to results of N-body simulations. These forms…

Cosmology and Nongalactic Astrophysics · Physics 2010-01-21 J. S. Bagla , Nishikanta Khandai , Girish Kulkarni

Full ray-tracing maps of gravitational lensing, constructed from N-Body simulations, represent a fundamental tool to interpret present and future weak lensing data. However the limitation of computational resources and storage capabilities…

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

Particle flow filters solve Bayesian inference problems by smoothly transforming a set of particles into samples from the posterior distribution. Particles move in state space under the flow of an McKean-Vlasov-Ito process. This work…

Optimization and Control · Mathematics 2025-05-02 Amit N Subrahmanya , Andrey A Popov , Adrian Sandu

We present an analytic model for the fully nonlinear power spectrum P and bispectrum Q of the cosmological mass density field. The model is based on physical properties of dark matter halos, with the three main model inputs being analytic…

Astrophysics · Physics 2009-06-16 Chung-Pei Ma , J. N. Fry

We address the amount of information in the non-Gaussian regime of weak lensing surveys by modelling all relevant covariances of the power spectra and bispectra, using 1000 ray-tracing simulation realizations for a Lambda-CDM model and an…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-09 Issha Kayo , Masahiro Takada , Bhuvnesh Jain
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