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Related papers: Dark matter caustics

200 papers

Astrophysical black holes are embedded in surrounding dark and baryonic matter that can measurably perturb the spacetime. We construct a self-consistent spacetime describing a slowly rotating black hole embedded in an external matter…

General Relativity and Quantum Cosmology · Physics 2026-02-12 Sayak Datta , Chiranjeeb Singha

The cold dark matter spectrum on earth is expected to have peaks in velocity space. We obtain estimates for the sizes and locations of these peaks. To this end we have generalized the secondary infall model of galactic halo formation to…

Astrophysics · Physics 2010-11-30 P. Sikivie , I. I. Tkachev , Yun Wang

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 presence of unseen halos of ``dark matter'' has long been inferred from the high rotation speeds of gas and stars in the outer parts of spiral galaxies$^{1}$. The volume density of this dark matter decreases less quickly from the…

Astrophysics · Physics 2009-10-22 Penny D. Sackett , Heather L. Morrison , Paul Harding , Todd A. Boroson

We study the dark and luminous mass distributions, circular velocity curves (CVC), line-of-sight kinematics, and angular momenta for a sample of 42 cosmological zoom simulations of massive galaxies. Using a temporal smoothing technique, we…

Cosmology and Nongalactic Astrophysics · Physics 2014-04-02 Xufen Wu , Ortwin Gerhard , Thorsten Naab , Ludwig Oser , Inma Martinez-Valpuesta , Michael Hilz , Eugene Churazov , Natalya Lyskova

Barred galaxies constitute about two thirds of observed disc galaxies. Bars affect not only the mass distribution of gas and stars, but also that of the dark matter. An elongation of the inner dark matter halo is known as the halo bar. We…

Astrophysics of Galaxies · Physics 2024-05-28 Daniel A. Marostica , Rubens E. G. Machado , E. Athanassoula , T. Manos

Reasons supporting the idea that most of the dark matter in galaxies and clusters of galaxies is baryonic are discussed. Moreover, it is argued that most of the dark matter in galactic halos should be in the form of MACHOs and cold…

Astrophysics · Physics 2007-05-23 F. De Paolis , Ph. Jetzer , G. Ingrosso , M. Roncadelli

We study the phase-space structure of a dark-matter halo formed in a high resolution simulation of a Lambda CDM cosmology. Our goal is to quantify how much substructure is left over from the inhomogeneous growth of the halo, and how it may…

Astrophysics · Physics 2009-09-25 Amina Helmi , Simon D. M. White , Volker Springel

We review most dynamical constraints on the gravitational field of spiral galaxies in general, and of the Milky Way in particular. Such constraints are of prime importance for determining the characteristics of the putative dark matter…

Astrophysics of Galaxies · Physics 2015-01-14 Benoit Famaey

Formation and disruption of dark-matter cusps are reviewed. Accumulation of baryons at the center of a halo can displace the dark matter, converting singular density cusps into low-density cores. The displaced mass can be of order 10 M_b…

Astrophysics · Physics 2007-05-23 David Merritt , Milos Milosavljevic

We carry out fully 3-dimensional simulations of evolution from self-similar, spherically symmetric linear perturbations of a Cold Dark Matter dominated Einstein-de Sitter universe. As a result of the radial orbit instability, the haloes…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Mark Vogelsberger , Roya Mohayaee , Simon D. M. White

A nonrelativistic quantum theory of dark matter particles in a spherical halo is developed by using a new asymmetric equation, which is complementary to the Schr\"odinger equation. The theory predicts that each dark matter halo has its core…

General Physics · Physics 2023-09-06 Z. E. Musielak

We present the basics of microlensing and give an overview of the results obtained so far. We also describe a scenario in which dark clusters of MACHOs (Massive Astrophysical Compact Halo Objects) and cold molecular clouds (mainly of $H_2$)…

Astrophysics · Physics 2009-10-31 Ph. Jetzer

In unified field theory the cosmological model of the universe has supersymmetric fields. Supersymmetric particles as dark and normal matter in galaxy clusters have a phase separation. Dark matter in halos have a statistical physics…

General Physics · Physics 2008-05-16 Ajay Patwardhan

According to the now strongly supported concordance $\Lambda$CDM model, galaxies may be grossly described as a luminous component embedded in a dark matter halo. The density profile of these mass dominating haloes may be determined by N -…

Cosmology and Nongalactic Astrophysics · Physics 2014-02-04 A. Del Popolo , V. F. Cardone

In two previous papers (Salvador-Sol\'e 2012a,b), it was shown that: i) the typical structural and kinematic properties of haloes in (bottom-up) hierarchical cosmologies endowed with random Gaussian density perturbations of dissipationless…

Cosmology and Nongalactic Astrophysics · Physics 2012-03-20 Eduard Salvador-Solé , Sinue Serra , Alberto Manrique

We considered a vacuum polarization inside a galaxy in the eikonal approximation and found that two possible types of polarization exist. The first type is described by the equation of state $p=\rho/3$, similar to radiation. Using the…

General Relativity and Quantum Cosmology · Physics 2022-09-05 Sergey L. Cherkas , Vladimir L. Kalashnikov

We investigate the caustic topologies for binary gravitational lenses made up of two objects whose gravitational potential declines as $1/r^n$. With $n<1$ this corresponds to power-law dust distributions like the singular isothermal sphere.…

General Relativity and Quantum Cosmology · Physics 2016-04-06 V. Bozza , C. Melchiorre

We continue the study of the tensor-four-scalars theory which is a modification of general relativity. We include normal matter by applying the displace, cut, and reflect method to our previous vacuum solutions with dark halo. The resulting…

General Relativity and Quantum Cosmology · Physics 2012-05-22 Günter Scharf

A new scenario for creation of galactic magnetic fields is proposed which is operative at the cosmological epoch of the galaxy formation, and which relies on unconventional properties of dark matter. Namely, it requires existence of feeble…

Cosmology and Nongalactic Astrophysics · Physics 2013-12-09 Zurab Berezhiani , A. D. Dolgov , I. I. Tkachev