Possible Evidence of Thermodynamic Equilibrium in Dark Matter Haloes
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In this article, the authors deduced the density profiles and gravitational potential functions of eight galaxies from the rotation velocity data from THINGS, and found that the density decreases exponentially with the potential in substantial regions of the haloes.Abstract:
After deducing the density profiles and gravitational potential functions of eight galaxies from the rotation velocity data from THINGS, we find that the density decreases exponentially with the potential in substantial regions of the haloes. Such behavior is in agreement with that of a single-component isothermal Boltzmann gas, and suggests that an effective description in terms of a Boltzmann gas is possible for dark matter in these regions. This could be an indication that dark matter self-interactions are sufficient in strength and number to lead to thermal equilibrium in these regions. We write down the dynamics and boundary conditions for a Boltzmann gas description and examine some of its qualitative and quantitative consequences. Solutions to the dynamical system are determined by three dimensionfull parameters, and provide reasonable fits to the rotational velocity data in the regions where the Boltzmann-like behavior was found. Unlike in the usual approach to curve fitting, we do not assume a specific form for the dark matter density profile and we do not require a detailed knowledge of the baryonic content of the galaxy.read more
Citations
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The age–velocity dispersion relation of the Galactic discs from LAMOST–Gaia data
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References
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A Universal Density Profile from Hierarchical Clustering
TL;DR: In this article, the authors used high-resolution N-body simulations to study the equilibrium density profiles of dark matter halos in hierarchically clustering universes, and they found that all such profiles have the same shape, independent of the halo mass, the initial density fluctuation spectrum, and the values of the cosmological parameters.
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Things:the hi nearby galaxy survey
Fabian Walter,Elias Brinks,W. J. G. de Blok,Frank Bigiel,Robert C. Kennicutt,Michele D. Thornley,Adam Leroy +6 more
TL;DR: The HI Nearby Galaxy Survey (THINGS) as discussed by the authors is a high spectral (≤52kms −1 ) and spatial (∼ 6 ′′ ) resolution survey of HI emission in 34 nearby galaxies obtained using the NRAO Very Large Array (VLA).
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High-resolution rotation curves and galaxy mass models from THINGS
TL;DR: In this article, rotation curves of 19 galaxies from the H I Nearby Galaxy Survey (THINGS) were used to derive the geometric and dynamical parameters using H I data alone and the rotation curves were combined with 3.6 μm data from the Spitzer Infrared Nearby Galaxies Survey to construct mass models.
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Dark and luminous matter in things dwarf galaxies
TL;DR: In this article, mass models for the dark matter component of seven dwarf galaxies taken from 'The H I Nearby Galaxy Survey' (THINGS) and compare these with those taken from numerical {Lambda} cold dark matter (LambDA}CDM) simulations are presented.
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Halo Properties in Cosmological Simulations of Self-Interacting Cold Dark Matter
TL;DR: In this paper, a comparison of halo properties in cosmological simulations of collisionless cold dark matter and self-interacting dark matter (SIDM) for a range of dark matter cross sections is presented.