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Related papers: Dark matter phase space densities

200 papers

We highlight the general scenario of dark matter freeze-out whilst the energy density of the universe is dominated by a decoupled non-relativistic species. Decoupling during matter domination changes the freeze-out dynamics, since the…

High Energy Physics - Phenomenology · Physics 2025-11-06 Saleh Hamdan , James Unwin

A halo model is presented which possesses a constant phase space density (Q) core followed by a radial CDM-like power law decrease in Q. The motivation for the core is the allowance for a possible primordial phase space density limit such…

Astrophysics · Physics 2009-11-13 F. D. A. Hartwick

We perform a general computational analysis of possible post-collision mass distributions in high-speed galaxy cluster collisions in the presence of weakly self-interacting dark matter. Using this analysis, we show that weakly…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-14 Yuriy Mishchenko , Chueng-Ryong Ji

Molecular cooling is essential for studying the formation of sub-structure of dissipative dark-matter halos that may host compact objects such as black holes. Here, we analyze the reaction rates relevant for the formation, dissociation, and…

Cosmology and Nongalactic Astrophysics · Physics 2022-08-09 Michael Ryan , James Gurian , Sarah Shandera , Donghui Jeong

We argue that the stellar velocity dispersion observed in an elliptical galaxy is a good proxy for the halo velocity dispersion. As dark matter halos are almost completely characterized by a single scale parameter, the stellar velocity…

Astrophysics of Galaxies · Physics 2015-11-17 Paul L. Schechter

Gravitational potential fluctuations driven by bursty star formation can kinematically 'heat up' dark matter at the centres of dwarf galaxies. A key prediction of such models is that, at a fixed dark matter halo mass, dwarfs with a higher…

Astrophysics of Galaxies · Physics 2019-04-15 J. I. Read , M. G. Walker , P. Steger

We attempt to estimate the uncertainty in the constraints on the spin independent dark matter-nucleon cross section due to our lack of knowledge of the dark matter phase space in the galaxy. We fit the density of dark matter before…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Malcolm Fairbairn , Tom Douce , Jace Swift

Dark matter (DM) capture in stars offers a rich phenomenology that makes it possible to probe a wide variety of particle DM scenarios in diverse astrophysical environments. In spite of decades of improvements to refine predictions of…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-02 José Lopes , Thomas Lacroix , Ilídio Lopes

This work continues the construction of a recently proposed model of dark matter stars. In this model, dark matter quanta are sterile massless particles that are emitted from the central regions of the galaxy in the radial direction. As a…

General Physics · Physics 2022-01-21 Igor Nikitin

A sizable fraction of the total energy density of the universe may be in heavy particles with a net dark $U(1)'$ charge comparable to its mass. When the charges have the same sign the cancellation between their gravitational and gauge…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-23 Nemanja Kaloper , Antonio Padilla

The most luminous galaxies in the present Universe are found at the centers of the most massive dark matter haloes, rich galaxy clusters. In the LCDM cosmology, such massive halo cores are present at redshift z=6 with a comoving number…

Astrophysics · Physics 2009-09-25 Liang Gao , Abraham Loeb , P. J. E. Peebles , Simon D. M. White , Adrian Jenkins

Various laboratory-based experiments are underway attempting to detect dark matter directly. The event rates and detailed signals expected in these experiments depend on the dark matter phase space distribution on sub-milliparsec scales.…

Astrophysics · Physics 2011-08-31 Daniele S. M. Fantin , Michael R. Merrifield , Anne M. Green

Although a simple argument implies that the distribution of dark matter in galactic halos is characterized by discrete flows and caustics, their presence is often ignored in discussions of galactic dynamics and of dark matter detection…

Astrophysics · Physics 2008-11-26 Aravind Natarajan , Pierre Sikivie

We develop a theoretical framework for describing the hierarchical structure of the phase space of cold dark matter haloes, due to gravitationally bound substructures. Because it includes the full hierarchy of the cold dark matter initial…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Niayesh Afshordi , Roya Mohayaee , Edmund Bertschinger

The relic abundance of thermal dark matter particles is generally assumed to be inversely proportional to their annihilation rate, which is therefore constrained by the present matter density, <sigma v> ~ 10^{-26} Omega_{dm}^{-1} cm^3…

Cosmology and Nongalactic Astrophysics · Physics 2010-01-07 Leonid Chuzhoy

Current data suggest that the central mass densities $\rho_0$ and phase-space densities $Q\equiv\rho_0/\sigma_V^3$ of cosmological halos in the present universe are correlated with their velocity dispersions $\sigma_V$ over a very wide…

Astrophysics · Physics 2009-11-06 Paul R. Shapiro , Ilian T. Iliev

The role of dark matter halos in galaxy disk evolution is reviewed, in particular the stabilisation of disks through self-gravity reduction, or the bar development through angular momentum exchange. Triaxial dark halos tend to weaken bars.…

Cosmology and Nongalactic Astrophysics · Physics 2012-10-19 F. Combes

Determining the structure of galaxy clusters is essential for an understanding of large scale structure in the universe, and may hold important clues to the identity and nature of dark matter particles. Moreover, the core dark matter…

Astrophysics · Physics 2009-11-07 J. S. Arabadjis , M. W. Bautz , G. Arabadjis

Adaptive SPH and N-body simulations were carried out to study the evolution of the equilibrium structure of dark matter halos that result from the gravitational instability and fragmentation of cosmological pancakes. Such halos resemble…

Astrophysics · Physics 2009-11-06 Marcelo Alvarez , Paul R. Shapiro , Hugo Martel

If the dark matter is part of a hidden sector with only very feeble couplings to the Standard Model, the lightest particle in the hidden sector will generically be long-lived and could come to dominate the energy density of the universe…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-20 Carlos Blanco , M. Sten Delos , Adrienne L. Erickcek , Dan Hooper