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Related papers: Light Dark Matter

200 papers

Dark matter (DM) constitutes around a 25% of the Universe, while baryons only a 4%. DM can be reasonably assumed to be made of particles, and many theories (Super-symmetry, Universal Extra Dimensions, etc.) predict Weakly Interacting…

High Energy Astrophysical Phenomena · Physics 2022-03-02 A. Morselli , B. Canadas , V. Vitale

The observation of a strong and extended positron-electron line annihilation emission in the central regions of the Galaxy by INTEGRAL-SPI, consistent with the Galactic bulge geometry, without any counterpart in the gamma-ray range, neither…

Astrophysics · Physics 2009-11-10 M. Cassé , B. Cordier , J. Paul , S. Schanne

The SPI instrument on-board the ESA/INTEGRAL satellite is engaged in a mission-long study of positron annihilation radiation from the Galaxy. Early results suggest that the disk component is only weakly detected at 511 keV by SPI. We review…

Astrophysics · Physics 2009-11-11 Peter A. Milne

Annihilating dark matter particles produce roughly as much power in electrons and positrons as in gamma ray photons. The charged particles lose essentially all of their energy to inverse Compton and synchrotron processes in the galactic…

Astrophysics · Physics 2009-11-10 E. A. Baltz , L. Wai

The Milky Way halo is the brightest source of dark matter annihilation on the sky. Indeed, the potential strength of the Galactic dark matter signal can supersede that expected from dwarf galaxies and galaxy groups even in regions away from…

Cosmology and Nongalactic Astrophysics · Physics 2018-12-20 Laura J. Chang , Mariangela Lisanti , Siddharth Mishra-Sharma

We analyze the first two years of data from the Fermi Gamma Ray Space Telescope from the direction of the inner 10 degrees around the Galactic Center with the intention of constraining, or finding evidence of, annihilating dark matter. We…

High Energy Physics - Phenomenology · Physics 2015-03-17 Dan Hooper , Lisa Goodenough

We use recently released data on the positron-to-electron ratio in cosmic rays from the AMS-02 experiment to constrain dark matter annihilation in the Milky Way. Due to the yet unexplained positron excess, limits are generally weaker than…

High Energy Physics - Phenomenology · Physics 2013-10-31 Joachim Kopp

Among various approaches for indirect detection of dark matter, synchrotron emission due to secondary electrons/positrons produced in galactic WIMPs annihilation is raising an increasing interest. In this paper we propose a new method to…

High Energy Astrophysical Phenomena · Physics 2010-01-15 Enrico Borriello , Giuseppe Longo , Gennaro Miele , Maurizio Paolillo , Beatriz B. Siffert , Fatemeh S. Tabatabaei , Rainer Beck

With 20 years of INTEGRAL/SPI observations, Yoneda et al. (2025) created the most detailed map of the positron annihilation line at 511keV. While central bulge and extended disk are readily recognised in this map, several hotspots at high…

High Energy Astrophysical Phenomena · Physics 2026-05-21 Thomas Siegert , Hiroki Yoneda

Annihilating dark matter (DM) models based on a scalar hidden sector with Higgs portal-like couplings to the Standard Model are considered as a possible explanation for recently observed cosmic ray excesses. Two versions of the model are…

High Energy Physics - Phenomenology · Physics 2015-05-13 Kazunori Kohri , John McDonald , Narendra Sahu

It has been recently proposed that the observed 511 keV emission from the Galactic bulge could be the product of very light (1-100 MeV) annihilating dark matter particles. Other possible explanations for this signal are associated with…

The Milky Way (MW) dwarf spheroidal satellite galaxies (dSphs) are particularly intriguing targets to search for gamma rays from Weakly Interacting Massive Particle (WIMP) dark matter (DM) annihilation or decay. They are nearby,…

High Energy Astrophysical Phenomena · Physics 2023-11-10 Alex McDaniel , Marco Ajello , Christopher M. Karwin , Mattia Di Mauro , Alex Drlica-Wagner , Miguel A. Sanchez-Conde

Data from the Fermi Large Area Telescope suggests that there is an extended excess of GeV gamma-ray photons in the Inner Galaxy. Identifying potential astrophysical sources that contribute to this excess is an important step in verifying…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Samuel K. Lee , Mariangela Lisanti , Benjamin R. Safdi

The flux of high-energy astrophysical $\gamma$ rays is attenuated by the production of electron-positron pairs from scattering off of extragalactic background light (EBL). We use the most up-to-date information on galaxy populations to…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-25 José Luis Bernal , Andrea Caputo , Gabriela Sato-Polito , Jordan Mirocha , Marc Kamionkowski

The dark matter (DM) density profile in the innermost region of the Galaxy remains an open question. In particular, while adiabatic growth of the supermassive black hole Sgr A$^\ast$ at the Galactic Center (GC) can induce a 'spike' in…

High Energy Physics - Phenomenology · Physics 2026-02-27 Dibya S. Chattopadhyay , P. S. Bhupal Dev , Yago Porto

Recent results from the PAMELA experiment indicate an excess in the positron spectrum above 10 GeV, but anti-proton data are consistent with the expected astrophysical backgrounds. We propose a scenario that reproduces these features. Dark…

High Energy Physics - Phenomenology · Physics 2009-09-24 Daniel J. Phalen , Aaron Pierce , Neal Weiner

In addition to gamma-rays, dark matter annihilation products can include energetic electrons which inverse Compton scatter with the cosmic microwave background to produce a diffuse extragalactic background of gamma-rays and X-rays. In…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-13 Alexander V. Belikov , Dan Hooper

Taking into account spins, we classify all two-body non-relativistic Dark Matter annihilation channels to the allowed polarization states of Standard Model particles, computing the energy spectra of the stable final-state particles relevant…

High Energy Physics - Phenomenology · Physics 2013-10-07 Marco Cirelli , Mario Kadastik , Martti Raidal , Alessandro Strumia

We are at the dawn of a data-driven era in astrophysics and cosmology. A large number of ongoing and forthcoming experiments combined with an increasingly open approach to data availability offer great potential in unlocking some of the…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-14 Siddharth Mishra-Sharma

The Fermi experiment has measured the cosmic ray electron+positron spectrum and positron fraction [$\Phi_{e^+}/(\Phi_{e^+ + e^-})]$, and PAMELA has measured the positron fraction with better precision. While the majority of cosmic ray…

Cosmology and Nongalactic Astrophysics · Physics 2013-04-04 Arjun Sharma