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Title: Make dark matter charged again

Abstract

We revisit constraints on dark matter that is charged under a U(1) gauge group in the dark sector, decoupled from Standard Model forces. We find that the strongest constraints in the literature are subject to a number of mitigating factors. For instance, the naive dark matter thermalization timescale in halos is corrected by saturation effects that slow down isotropization for modest ellipticities. The weakened bounds uncover interesting parameter space, making models with weak-scale charged dark matter viable, even with electromagnetic strength interaction. This also leads to the intriguing possibility that dark matter self-interactions within small dwarf galaxies are extremely large, a relatively unexplored regime in current simulations. Such strong interactions suppress heat transfer over scales larger than the dark matter mean free path, inducing a dynamical cutoff length scale above which the system appears to have only feeble interactions. These effects must be taken into account to assess the viability of darkly-charged dark matter. Future analyses and measurements should probe a promising region of parameter space for this model.

Authors:
; ; ;  [1]
  1. Department of Physics, Harvard University, Cambridge, MA 02138 (United States)
Publication Date:
OSTI Identifier:
22676219
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2017; Journal Issue: 05; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; GALAXIES; GAUGE INVARIANCE; HEAT TRANSFER; MEAN FREE PATH; NONLUMINOUS MATTER; SATURATION; SIMULATION; SPACE; STANDARD MODEL; STRONG INTERACTIONS; THERMALIZATION; U-1 GROUPS; VIABILITY

Citation Formats

Agrawal, Prateek, Cyr-Racine, Francis-Yan, Randall, Lisa, and Scholtz, Jakub, E-mail: prateekagrawal@fas.harvard.edu, E-mail: fcyrraci@physics.harvard.edu, E-mail: randall@physics.harvard.edu, E-mail: jscholtz@physics.harvard.edu. Make dark matter charged again. United States: N. p., 2017. Web. doi:10.1088/1475-7516/2017/05/022.
Agrawal, Prateek, Cyr-Racine, Francis-Yan, Randall, Lisa, & Scholtz, Jakub, E-mail: prateekagrawal@fas.harvard.edu, E-mail: fcyrraci@physics.harvard.edu, E-mail: randall@physics.harvard.edu, E-mail: jscholtz@physics.harvard.edu. Make dark matter charged again. United States. doi:10.1088/1475-7516/2017/05/022.
Agrawal, Prateek, Cyr-Racine, Francis-Yan, Randall, Lisa, and Scholtz, Jakub, E-mail: prateekagrawal@fas.harvard.edu, E-mail: fcyrraci@physics.harvard.edu, E-mail: randall@physics.harvard.edu, E-mail: jscholtz@physics.harvard.edu. Mon . "Make dark matter charged again". United States. doi:10.1088/1475-7516/2017/05/022.
@article{osti_22676219,
title = {Make dark matter charged again},
author = {Agrawal, Prateek and Cyr-Racine, Francis-Yan and Randall, Lisa and Scholtz, Jakub, E-mail: prateekagrawal@fas.harvard.edu, E-mail: fcyrraci@physics.harvard.edu, E-mail: randall@physics.harvard.edu, E-mail: jscholtz@physics.harvard.edu},
abstractNote = {We revisit constraints on dark matter that is charged under a U(1) gauge group in the dark sector, decoupled from Standard Model forces. We find that the strongest constraints in the literature are subject to a number of mitigating factors. For instance, the naive dark matter thermalization timescale in halos is corrected by saturation effects that slow down isotropization for modest ellipticities. The weakened bounds uncover interesting parameter space, making models with weak-scale charged dark matter viable, even with electromagnetic strength interaction. This also leads to the intriguing possibility that dark matter self-interactions within small dwarf galaxies are extremely large, a relatively unexplored regime in current simulations. Such strong interactions suppress heat transfer over scales larger than the dark matter mean free path, inducing a dynamical cutoff length scale above which the system appears to have only feeble interactions. These effects must be taken into account to assess the viability of darkly-charged dark matter. Future analyses and measurements should probe a promising region of parameter space for this model.},
doi = {10.1088/1475-7516/2017/05/022},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 05,
volume = 2017,
place = {United States},
year = {Mon May 01 00:00:00 EDT 2017},
month = {Mon May 01 00:00:00 EDT 2017}
}
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