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Related papers: Relaxing constraints on dark matter annihilation

200 papers

If even a relatively small number of black holes were created in the early universe, they will constitute an increasingly large fraction of the total energy density as space expands. It is thus well-motivated to consider scenarios in which…

High Energy Physics - Phenomenology · Physics 2019-09-04 Dan Hooper , Gordan Krnjaic , Samuel D. McDermott

Mass bounds on dark matter (DM) candidates are obtained for particles decoupling in or out of equilibrium with {\bf arbitrary} isotropic and homogeneous distribution functions. A coarse grained Liouville invariant primordial phase space…

Astrophysics · Physics 2008-11-26 D. Boyanovsky , H. J. de Vega , N. Sanchez

We study a nonstandard dark-matter thermal history in which strong self-interactions give rise to collective many-body effects at high number density, as in strongly interacting quantum media. At early times, dark matter occupies a…

High Energy Physics - Phenomenology · Physics 2026-03-11 Hindi Zouhair

The Lightest Supersymmetric Particle predicted in most of the supersymmetric scenarios is an ideal candidate for the dark matter of cosmology. Their detection is of extreme significance today. Recently there have been intriguing signals of…

Astrophysics · Physics 2007-05-23 Afsar Abbas

Light dark matter annihilating into electron-positron pairs emits a significant amount of internal bremsstrahlung that may contribute to the cosmic gamma-ray background. The amount of emitted gamma-rays depends on the dark matter clumping…

We conduct a comprehensive analysis of potential annihilation processes of light dark matter (DM) in minimal Higgs portal models near supermassive black hole (Sgr A$^{\star}$) in the Galactic Center, considering interactions between DM…

High Energy Physics - Phenomenology · Physics 2025-01-14 Chih-Ting Lu , Xiao-Yi Luo , Zi-Qing Xia

The early universe could feature multiple reheating events, leading to jumps in the visible sector entropy density that dilute both particle asymmetries and the number density of frozen-out states. In fact, late time entropy jumps are…

High Energy Physics - Phenomenology · Physics 2017-03-08 Joseph Bramante , James Unwin

The minimal supersymmetric setup offers a comprehensive framework to interpret the Fermi LAT Galactic center excess. Taking into account experimental, theoretical, and astrophysical uncertainties we can identify valid parameter regions…

High Energy Physics - Phenomenology · Physics 2017-09-06 Anja Butter , Simona Murgia , Tilman Plehn , Tim M. P. Tait

Recently, some very tight constraints of annihilating dark matter have been obtained from gamma-ray data of the Milky Way and Milky Way dwarf spheroidal satellite galaxies. In this article, we report that there are two excellent galaxy…

High Energy Astrophysical Phenomena · Physics 2017-11-15 Man Ho Chan , Chung Hei Leung

If the temperature of the hot thermal plasma in the Early Universe was within a few orders of magnitude of the Planck scale $M_{\rm Pl}$, then the hoop conjecture predicts the formation of microscopic black holes from particle collisions in…

High Energy Physics - Phenomenology · Physics 2023-10-03 Avi Friedlander , Ningqiang Song , Aaron C. Vincent

If the dark matter is produced in the early universe prior to Big Bang nucleosynthesis, a modified cosmological history can drastically affect the abundance of relic dark matter particles. Here, we assume that an additional species to…

High Energy Physics - Phenomenology · Physics 2018-02-26 Francesco D'Eramo , Nicolas Fernandez , Stefano Profumo

We investigate the dark matter annihilation in the brane-world and quintessence scenarios, in which the modified cosmological expansion rate can enhance the thermal relic density of dark matter. According to the observed dark matter…

High Energy Physics - Phenomenology · Physics 2009-07-09 Wan-Lei Guo , Xin Zhang

Analytical calculations and recent numerical experiments have shown that a sizable of the mass in our Galaxy is in a form of clumpy, virialized substructures that, according to \cite{dms:05}, can be as light as $10^{-6} \msun$. In this work…

Astrophysics · Physics 2009-11-11 Lidia Pieri , Enzo Branchini , Stefan Hofmann

We demonstrate a novel mechanism for producing dark compact objects and black holes through a dark sector, where all the dark matter can be dissipative. Heavy dark sector particles with masses above $10^4$ GeV can come to dominate the…

High Energy Physics - Phenomenology · Physics 2024-08-29 Joseph Bramante , Christopher V. Cappiello , Melissa D. Diamond , J. Leo Kim , Qinrui Liu , Aaron C. Vincent

The dark-matter candidates of particle physics invariably possess electromagnetic interactions, if only via quantum fluctuations. Taken en masse, dark matter can thus engender an index of refraction which deviates from its vacuum value. Its…

High Energy Physics - Phenomenology · Physics 2014-11-18 S. Gardner , D. C. Latimer

We explore the viability of a boson dark matter candidate with an asymmetry between the number densities of particles and antiparticles. A simple thermal field theory analysis confirms that, under certain general conditions, this component…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-27 Anthony Aguirre , Alberto Diez-Tejedor

The large gap between a galactic dark matter subhalo's velocity and its own gravitational binding velocity creates the situation that small subhalos can be evaporated before dark matter thermalize with baryons due to the low binding…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-20 Xiao-jun Bi , Yu Gao , Mingjie Jin , Yugen Lin , Qian-Fei Xiang

In the cosmological paradigm, cold dark matter (DM) dominates the mass content of the Universe and is present at every scale. Candidates for DM include many extensions of the Standard Model with weakly interacting massive particles (WIMPs)…

High Energy Astrophysical Phenomena · Physics 2017-08-25 Benjamin Zitzer , VERITAS Collaboration

We investigate cosmological implications of an energy density contribution arising by elastic dark matter self-interactions. Its scaling behaviour shows that it can be the dominant energy contribution in the early universe. Constraints from…

Cosmology and Nongalactic Astrophysics · Physics 2011-04-06 Rainer Stiele , Tillmann Boeckel , Jurgen Schaffner-Bielich

We make use of the phase space density approach to discuss gravitino as a warm dark matter candidate. Barring fine tuning between the reheat temperature in the Universe and superparticle masses, we find that \emph{warm} gravitinos have both…

High Energy Physics - Phenomenology · Physics 2009-02-09 D. Gorbunov , A. Khmelnitsky , V. Rubakov