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Related papers: Exciting dark matter in the galactic center

200 papers

Employing Fermi-LAT gamma ray observations, several independent groups have found excess extended gamma ray emission at the Galactic center (GC). Both, annihilating dark matter (DM) or a population of $\sim 10^3$ unresolved millisecond…

High Energy Astrophysical Phenomena · Physics 2013-12-12 Chris Gordon , Oscar Macias

It was recently proposed that stable particles of charge $-2$, $O^{--}$, can exist and constitute dark matter after they bind with primordial helium in O-helium (OHe) atoms. We study here in details the possibility that this model provides…

High Energy Physics - Phenomenology · Physics 2014-01-22 Jean-René Cudell , Maxim Yu. Khlopov , Quentin Wallemacq

Both the robust INTEGRAL 511 keV gamma-ray line and the recent tentative hint of the 135 GeV gamma-ray line from Fermi-LAT have similar signal morphologies, and may be produced from the same dark matter annihilation. Motivated by this…

High Energy Physics - Phenomenology · Physics 2015-06-12 Yang Bai , Meng Su , Yue Zhao

The presence of dark matter is nowadays widely supported by a large body of astronomical and cosmological observations. A large amount of dark matter is expected to be present in the central region of the Milky Way. Very-high-energy (>100…

High Energy Astrophysical Phenomena · Physics 2019-08-14 Lucia Rinchiuso , Emmanuel Moulin , Aion Viana , Christopher Van Eldik , Johannes Veh

We explore the $511$~keV emission associated to sub-GeV dark matter (DM) particles that can produce electron-positron pairs and form positronium after thermalizing. We use $\sim16$~yr of SPI data from INTEGRAL to constrain DM properties,…

High Energy Physics - Phenomenology · Physics 2026-03-24 Pedro De la Torre Luque , Shyam Balaji , Joseph Silk

The presence of dark matter (DM) is suggested by a wealth of astrophysical and cosmological measurements. However, its underlying nature is yet unknown. Among the most promising candidates are weakly interacting massive particles (WIMPs):…

High Energy Astrophysical Phenomena · Physics 2021-08-25 A. Montanari , E. Moulin , D. Malyshev

An excess of 511 keV photons has been detected from the central region of the Milky Way. It has been suggested that the positrons responsible for this signal could be produced through the Hawking evaporation of primordial black holes. After…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-11 Celeste Keith , Dan Hooper

The Milky Way's Galactic Center harbors a gamma-ray excess that is a candidate signal of annihilating dark matter. Dwarf galaxies remain predominantly dark in their expected commensurate emission. In this work we quantify the degree of…

High Energy Astrophysical Phenomena · Physics 2018-05-16 Ryan E. Keeley , Kevork N. Abazajian , Anna Kwa , Nicholas L. Rodd , Benjamin R. Safdi

Recent preliminary results from the PAMELA experiment indicate the presence of an excess of cosmic ray positrons above 10 GeV. In this letter, we consider possibility that this signal is the result of dark matter annihilations taking place…

High Energy Physics - Phenomenology · Physics 2009-12-30 Ilias Cholis , Lisa Goodenough , Dan Hooper , Melanie Simet , Neal Weiner

Many theories of dark matter (DM) predict that DM particles can be captured by stars via scattering on ordinary matter. They subsequently condense into a DM core close to the center of the star and eventually annihilate. In this work, we…

High Energy Physics - Phenomenology · Physics 2017-04-04 Vedran Brdar , Joachim Kopp , Jia Liu

We consider the signals of positrons and electrons from "exciting" dark matter (XDM) annihilation. Because of the light (m_phi ~< 1 GeV) force carrier phi into which the dark matter states can annihilate, the electrons and positrons are…

Astrophysics · Physics 2009-07-06 Ilias Cholis , Lisa Goodenough , Neal Weiner

Recent evidence for an excess of gamma rays in the GeV energy range about the Galactic Center have refocused attention on models of dark matter in the low mass regime ($m_\chi \lesssim m_Z/2$). Because this is an experimentally well-trod…

High Energy Physics - Phenomenology · Physics 2015-08-21 Jia Liu , Neal Weiner , Wei Xue

Persistent excesses in the spectra of gamma rays from the galactic center and cosmic ray antiprotons can be explained by dark matter of mass $50\sim 65$\,GeV annihilating into $b$ quarks, but this is typically hard to reconcile with direct…

High Energy Physics - Phenomenology · Physics 2019-08-28 James M. Cline , Takashi Toma

Several cosmic ray experiments have measured excesses in electrons and positrons, relative to standard backgrounds, for energies from ~ 10 GeV - 1 TeV. These excesses could be due to new astrophysical sources, but an explanation in which…

High Energy Astrophysical Phenomena · Physics 2014-11-20 Spencer Chang , Lisa Goodenough

Tentative evidence of a 3.5 keV X-ray line has been found in the stacked spectra of galaxy clusters, individual clusters, the Andromeda galaxy and the galactic center, leading to speculation that it could be due to decays of metastable dark…

Cosmology and Nongalactic Astrophysics · Physics 2015-01-09 James M. Cline , Andrew R. Frey

In light of the excess in the low-energy electron recoil events reported by XENON1T, many new physics scenarios have been proposed as a possible origin of the excess. One possible explanation is that the excess is a result of a fast moving…

High Energy Physics - Phenomenology · Physics 2020-12-30 R. Primulando , J. Julio , P. Uttayarat

The recent high energy electron and positron flux observed by the DAMPE experiment indicates possible excess events near 1.4 TeV. Such an excess may be evidence of dark matter annihilations or decays in a dark matter subhalo that is located…

High Energy Physics - Phenomenology · Physics 2018-08-22 Xuewen Liu , Zuowei Liu

Recent reports of a gamma-ray line feature at ~130 GeV in data from the Fermi Gamma-Ray Space Telescope have generated a great deal of interest in models in which dark matter particles annihilate with a sizable cross section to final states…

High Energy Physics - Phenomenology · Physics 2013-05-30 Matthew R. Buckley , Dan Hooper

We construct empirical models of the diffuse gamma-ray background toward the Galactic Center. Including all known point sources and a template of emission associated with interactions of cosmic rays with molecular gas, we show that the…

High Energy Astrophysical Phenomena · Physics 2014-07-23 Kevork N. Abazajian , Nicolas Canac , Shunsaku Horiuchi , Manoj Kaplinghat

Galactic weak-scale Dark Matter (DM) particles annihilating into lepton-rich channels not only produce gamma-rays via prompt radiation but also generate abundant energetic electrons and positrons, which subsequently emit through…

High Energy Physics - Phenomenology · Physics 2025-10-09 Marco Cirelli , Arpan Kar