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Related papers: Gamma-Ray Lines from Radiative Dark Matter Decay

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Recently, tentative evidence for an excess of gamma rays at energies around 130 GeV has been reported from analyses of data from the Fermi Large Area Telescope (LAT). The excess is potentially of great interest, as it could be associated…

High Energy Astrophysical Phenomena · Physics 2012-07-04 Stefano Profumo , Tim Linden

Nearby clusters and groups of galaxies are potentially bright sources of high-energy gamma-ray emission resulting from the pair-annihilation of dark matter particles. However, no significant gamma-ray emission has been detected so far from…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-25 LAT Collaboration

Recently, observations by PAMELA, the Fermi Gamma Ray Space Telescope, and other cosmic ray experiments have generated a great deal of interest in dark matter (DM) particles which annihilate at a high rate to leptons. In this letter, we…

Cosmology and Nongalactic Astrophysics · Physics 2009-06-01 Douglas Spolyar , Matthew Buckley , Katherine Freese , Dan Hooper , Hitoshi Murayama

We argue that we may be able to sort out dark matter models in which electrons are generated through the annihilation and/or decay of dark matter, by using a fact that the initial energy spectrum is reflected in the cosmic-ray electron flux…

The observation of a sharp spectral feature in the gamma-ray sky would be one of the cleanest ways to identify dark matter and pinpoint its properties. Over the years a lot of attention has been paid to two specific features, namely…

High Energy Physics - Phenomenology · Physics 2012-07-25 Alejandro Ibarra , Sergio López Gehler , Miguel Pato

The idea that dark matter forms part of a larger dark sector is very intriguing, given the high degree of complexity of the visible sector. In this paper, we discuss lepton jets as a promising signature of an extended dark sector. As a…

High Energy Physics - Phenomenology · Physics 2015-07-17 Malte Buschmann , Joachim Kopp , Jia Liu , Pedro A. N. Machado

Gamma-ray data from Fermi-LAT reveal a bi-lobular structure extending up to 50 degrees above and below the galactic centre, which presumably originated in some form of energy release there less than a few million years ago. It has been…

High Energy Astrophysical Phenomena · Physics 2011-08-26 Philipp Mertsch , Subir Sarkar

Dark matter captured by interaction with electrons inside the Sun may annihilate via long-lived mediator to produce observable gamma ray signals. We utilize solar gamma ray flux measurements from the Fermi Large Area Telescope and High…

High Energy Physics - Phenomenology · Physics 2022-06-15 Debajit Bose , Tarak Nath Maity , Tirtha Sankar Ray

We analyze the recently released Fermi-LAT data on the sum of electrons and positrons. Compared to a conventional, pre-Fermi, background model, a surprising excess in the several hundred GeV range is found and here we analyze it in terms of…

High Energy Astrophysical Phenomena · Physics 2009-09-02 Lars Bergstrom , Joakim Edsjo , Gabrijela Zaharijas

Dark matter annihilation into photons in our galaxy would constitute an exciting indirect signal of its existence, as underscored by tentative evidence for 130 GeV dark matter in Fermi/LAT data. Models that give a large annihilation cross…

High Energy Physics - Phenomenology · Physics 2013-11-11 James M. Cline , Grace Dupuis , Zuowei Liu

MMonochromatic neutrinos from dark matter annihilations ($\chi\chi\to \nu\bar\nu$) are always produced in association with a gamma-ray spectrum generated by electroweak bremsstrahlung. Consequently, these neutrino lines can be searched for…

High Energy Physics - Phenomenology · Physics 2016-07-06 Farinaldo S. Queiroz , Carlos E. Yaguna , Christoph Weniger

Due to their higher concentrations and small internal velocities, Milky Way subhalos can be at least as important as the smooth halo in accounting for the GeV positron excess via dark matter annihilation. After showing how this can be…

High Energy Astrophysical Phenomena · Physics 2010-08-13 Matthew D. Kistler , Jennifer M. Siegal-Gaskins

We present a search for gamma-ray emission from the direction of the newly discovered dwarf galaxy Reticulum II. Using Fermi-LAT data, we detect a signal that exceeds expected backgrounds between ~2-10 GeV and is consistent with…

The origin of the cosmic gamma-ray background at 1-20 MeV remains a mystery. We show that gamma-ray emission accompanying annihilation of 20 MeV dark matter particles explains most of the observed signal. Our model satisfies all of the…

Astrophysics · Physics 2009-11-13 Kyungjin Ahn , Eiichiro Komatsu

We study a scenario that a hidden gauge boson constitutes the dominant component of dark matter and decays into the standard model particles through a gauge kinetic mixing. Interestingly, gamma rays and positrons produced from the decay of…

High Energy Physics - Phenomenology · Physics 2009-01-16 Chuan-Ren Chen , Fuminobu Takahashi , T. T. Yanagida

X-ray and gamma-ray observations can help understand the origin of the electron and positron signals reported by ATIC, PAMELA, PPB-BETS, and Fermi. It remains unclear whether the observed high-energy electrons and positrons are produced by…

High Energy Astrophysical Phenomena · Physics 2012-04-03 Antoine Calvez , Warren Essey , Malcolm Fairbairn , Alexander Kusenko , Michael Loewenstein

From data recently reported from the IceCube telescope, we derive new bounds on the monochromatic neutrino signal produced from dark matter particle decays. In the few TeV to tens of TeV energy range, these bounds turn out to be better than…

High Energy Physics - Phenomenology · Physics 2015-12-23 Chaïmae El Aisati , Michael Gustafsson , Thomas Hambye

High energy gamma-rays and neutrinos can be produced both by the annihilation and by the possible slow decay of dark matter particles. We discuss the fluxes and spectra of such secondaries produced by dark matter particles in the universe…

Astrophysics · Physics 2009-10-28 F. W. Stecker

The diffuse gamma ray emission from astrophysical backgrounds in our Galaxy and the signal due to the annihilation or decay of Dark Matter (DM) in the Galactic Halo are expected to have a substantially different morphology and spectral…

High Energy Astrophysical Phenomena · Physics 2019-08-14 Gabrijela Zaharijas , Alessandro Cuoco , Zhaoyu Yang , Jan Conrad

Evidence for the existence of low energy cosmic rays in the Galaxy comes from the COMPTEL observations of gamma ray line emission from Orion, and also from light element abundance data which seem to suggest a low energy rather than a…

Astrophysics · Physics 2007-05-23 Reuven Ramaty
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