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Related papers: Cores in Dwarf Galaxies from Fermi Repulsion

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If dark matter is unstable and the mass is within GeV-TeV regime, its decays produce high-energy photons that give contribution to the extragalactic gamma-ray background (EGRB). We constrain dark matter decay by analyzing the 50-month EGRB…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Shin'ichiro Ando , Koji Ishiwata

Using 14 years of Fermi-LAT data and 10 years of H.E.S.S. observations in the direction of the galactic center, we derive limits on gamma-ray lines originated from dark matter annihilations for fermionic and scalar fields. We describe the…

High Energy Physics - Phenomenology · Physics 2026-03-10 Lucia Angel , Guillermo Gambini , Leticia Guedes , Farinaldo S. Queiroz , Vitor de Souza

Recently, it has been shown that electrons and positrons from dark matter (DM) annihilations provide an excellent fit to the Fermi, PAMELA, and HESS data. Using this DM model, which requires an enhancement of the annihilation cross section…

High Energy Astrophysical Phenomena · Physics 2009-11-20 Anders Pinzke , Christoph Pfrommer , Lars Bergstrom

We investigate constraints on the inner stellar density profile from photometric data of dwarf spheroidal and ultra-faint dwarf galaxies. Our aim is to clarify under what conditions cored stellar profiles require dark matter halos that are…

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

The core-cusp problem persists as an unresolved tension between the predictions of $\Lambda$CDM cosmology and observations of dark matter (DM) profiles in dwarf spheroidal and other galaxies. We present a novel scenario for converting cusps…

High Energy Physics - Phenomenology · Physics 2021-04-29 James M. Cline , Guillermo Gambini , Samuel D. McDermott , Matteo Puel

We analyze 2.8-yr data of 1-100 GeV photons for clusters of galaxies, collected with the Large Area Telescope onboard the Fermi satellite. By analyzing 49 nearby massive clusters located at high Galactic latitudes, we find no excess…

High Energy Astrophysical Phenomena · Physics 2012-07-09 Shin'ichiro Ando , Daisuke Nagai

In this letter, we consider a class of scenarios in which the dark matter is part of a heavy hidden sector that is thermally decoupled from the Standard Model in the early universe. The dark matter freezes-out by annihilating to a lighter,…

High Energy Physics - Phenomenology · Physics 2016-07-06 Asher Berlin , Dan Hooper , Gordan Krnjaic

We use observations of ultra-faint dwarf (UFD) galaxies to constrain the particle mass of ultra-light dark matter. Potential fluctuations created by wave interference in virialized "fuzzy" dark matter (FDM) halos dynamically heat stellar…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-22 Neal Dalal , Andrey Kravtsov

Recent discoveries of optical signatures of black holes in dwarf galaxies indicates that low-mass galaxies can indeed host intermediate massive black holes. This motivates the assessment of the resulting effect on the host dark matter…

High Energy Astrophysical Phenomena · Physics 2015-06-19 Alma X. Gonzalez-Morales , Stefano Profumo , Farinaldo S. Queiroz

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

We consider the possibility that dark matter halos are made of quantum particles such as fermions or bosons in the form of Bose-Einstein condensates. In that case, they generically have a "core-halo" structure with a quantum core that…

Cosmology and Nongalactic Astrophysics · Physics 2019-12-11 Pierre-Henri Chavanis

Warm dark matter (WDM) may resolve the possible conflict between observed galaxy halos and the halos produced in cold dark matter (CDM) simulations. Here we present an extension of MSSM to include WDM by adding a gauge singlet fermion,…

High Energy Physics - Phenomenology · Physics 2009-12-04 John McDonald , Narendra Sahu

High energy electrons and positrons from decaying dark matter can produce a significant flux of gamma rays by inverse Compton off low energy photons in the interstellar radiation field. This possibility is inevitably related with the dark…

High Energy Astrophysical Phenomena · Physics 2014-11-20 Le Zhang , Christoph Weniger , Luca Maccione , Javier Redondo , Guenter Sigl

We present a synthesis of recent photometric and kinematic data for several of the most dark-matter dominated galaxies. There is a bimodal distribution in half-light radii, with stable star clusters always being smaller than $\sim30$pc,…

Cold dark matter (CDM) models predict small-scale structure in excess of observations of the cores and abundance of dwarf galaxies. These problems might be solved, and the virtues of CDM models retained, even without postulating {\it ad…

Astrophysics · Physics 2009-10-31 Wayne Hu , Rennan Barkana , Andrei Gruzinov

Recent weak and strong lensing data of the galaxy cluster A1689 are modelled by dark fermions that are quantum degenerate within some core. The gas density, deduced from X-ray observations up to 1 Mpc and obeying a cored power law, is taken…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-28 Theo M. Nieuwenhuizen , Andrea Morandi

Current cosmological models and data suggest the existence of a Cold Dark Matter (DM) component, however the nature of DM particles remains unknown. A favored candidate for DM is a Weakly Interacting Massive Particle (WIMP) in the mass…

High Energy Astrophysical Phenomena · Physics 2019-08-13 Jeffrey Grube

The $\gamma$-ray and neutrino emissions from dark matter (DM) annihilation in galaxy clusters are studied. After about one year operation of Fermi-LAT, several nearby clusters are reported with stringent upper limits of GeV $\gamma$-ray…

High Energy Astrophysical Phenomena · Physics 2015-03-13 Qiang Yuan , Peng-Fei Yin , Xiao-Jun Bi , Xin-Min Zhang , Shou-Hua Zhu

Recent data from Reticulum II (RetII) require the energy range of the FermiLAT $\gamma$-excess to be $\sim$ $2-10$ GeV. We adjust our unified nonthermal Dark Matter (DM) model to accommodate this. We have two extra scalars beyond the…

High Energy Physics - Phenomenology · Physics 2016-02-11 Anirban Biswas , Debasish Majumdar , Probir Roy