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Related papers: Cosmic Ray Positrons from Annihilations into a New…

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In light of the mounting evidence that the highest energy cosmic rays are dominated by protons and not gamma-rays, we discuss the prospect that these cosmic rays are generated in the decay or annihilation of superheavy relic particles. We…

High Energy Physics - Phenomenology · Physics 2007-05-23 Francis Halzen , Dan Hooper

The PAMELA, Fermi and HESS experiments (PFH) have shown anomalous excesses in the cosmic positron and electron fluxes. A very exciting possibility is that those excesses are due to annihilating dark matter (DM). In this paper we calculate…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-02 Gert Huetsi , Andi Hektor , Martti Raidal

We give theoretical predictions for the radio emission of a dark matter candidate annihilating into 2-lepton and 4-lepton final states. We then compare our results with the known radio measurements of the sky temperature as a function of…

High Energy Physics - Phenomenology · Physics 2019-12-04 Elaine C. F. S. Fortes , Oswaldo D. Miranda , Floyd W. Stecker , Carlos A. Wuensche

Unexpected features in the energy spectra of cosmic rays electrons and positrons have been recently observed by PAMELA and Fermi-LAT satellite experiments, opening to the exciting possibility of an indirect manifestation of new physics. A…

High Energy Physics - Phenomenology · Physics 2015-05-28 Isabella Masina , Francesco Sannino

We investigate the relation between the annihilation of dark matter (DM) particles into lepton pairs and into 2-body final states including one or two photons. We parametrize the DM interactions with leptons in terms of contact…

High Energy Physics - Phenomenology · Physics 2015-09-03 Adam Coogan , Stefano Profumo , William Shepherd

In this paper we develop a Markov Chain Monte Carlo code to study the dark matter properties in interpreting the recent observations of cosmic ray electron/positron excesses. We assume that the dark matter particles couple dominantly to…

Cosmology and Nongalactic Astrophysics · Physics 2010-01-20 Jie Liu , Qiang Yuan , Xiaojun Bi , Hong Li , Xinmin Zhang

We propose a scenario where Dark Matter (DM) annihilates into an intermediate state which travels a distance $\lambda \equiv v/\Gamma$ on the order of galactic scales and then decays to Standard Model (SM) particles. The long lifetime…

High Energy Astrophysical Phenomena · Physics 2009-07-22 Ira Z. Rothstein , Thomas Schwetz , Jure Zupan

Excitation of multicomponent dark matter in the galactic center has been proposed as the source of low-energy positrons that produce the excess 511 keV gamma rays that have been observed by INTEGRAL. Such models have also been promoted to…

High Energy Physics - Phenomenology · Physics 2010-05-28 James M. Cline

Cosmologically long-lived, composite states arise as natural dark matter candidates in theories with a strongly interacting hidden sector at a scale of 10 - 100 TeV. Light axion-like states, with masses in the 1 MeV - 10 GeV range, are also…

High Energy Physics - Phenomenology · Physics 2010-05-28 Jeremy Mardon , Yasunori Nomura , Jesse Thaler

Multidimensional modification of gravity with a smaller mass scale of the gravitational interaction is considered. Stable by assumption dark matter particles could decay via interactions with virtual black holes. The decay rates of such…

High Energy Physics - Phenomenology · Physics 2023-12-12 E. V. Arbuzova , A. D. Dolgov , A. A. Nikitenko

Motivated by the recent results from the PAMELA and ATIC, we study the cosmic-ray electron and positron produced by the decay of gravitino dark matter. We calculate the cosmic-ray electron and positron fluxes and discuss implications to the…

High Energy Physics - Phenomenology · Physics 2016-11-15 Koji Ishiwata , Shigeki Matsumoto , Takeo Moroi

The positron excess observed by PAMELA and then confirmed by AMS 02 has intrigued the particle physics community since 2008. Various dark matter decay and annihilation models have been built to explain the excess. However, the bounds from…

High Energy Physics - Phenomenology · Physics 2019-05-01 Yasaman Farzan , Meshkat Rajaee

Dark matter candidates arising in models of particle physics incorporating weak scale supersymmetry may produce detectable signals through their annihilation into neutrinos, photons, or positrons. A large number of relevant experiments are…

Astrophysics · Physics 2009-10-09 Jonathan L. Feng , Konstantin T. Matchev , Frank Wilczek

The CoGeNT experiment, dedicated to direct detection of dark matter, has recently released excess events that could be interpreted as elastic collisions of $\sim$10 GeV dark matter particles, which might simultaneously explain the still…

High Energy Physics - Phenomenology · Physics 2011-10-17 David G. Cerdeno , Timur Delahaye , Julien Lavalle

We consider the process of scattering of Galactic cosmic-ray electrons and protons off of dark matter with the radiation of a final-state photon. This process provides a novel way to search for Galactic dark matter with gamma rays. We argue…

High Energy Physics - Phenomenology · Physics 2015-05-28 Stefano Profumo , Lorenzo Ubaldi

We analyze the cosmic-ray signatures of decaying gravitino dark matter in a model independent way based on an operator analysis. Thermal leptogenesis and universal boundary conditions at the GUT scale restrict the gravitino mass to be below…

High Energy Physics - Phenomenology · Physics 2009-09-16 Wilfried Buchmüller , Alejandro Ibarra , Tetsuo Shindou , Fumihiro Takayama , David Tran

Motivated by the gamma-ray excess observed from the region surrounding the Galactic Center, we explore particle dark matter models that could potentially account for the spectrum and normalization of this signal. Taking a model-independent…

High Energy Physics - Phenomenology · Physics 2015-06-04 Asher Berlin , Dan Hooper , Samuel D. McDermott

The recent data from PAMELA and Fermi-LAT can be interpreted as evidence of new astrophysical sources of high energy positrons. In that case, such astrophysical positrons constitute an additional background against the positrons from dark…

High Energy Physics - Phenomenology · Physics 2010-01-27 Ki-Young Choi , Carlos E. Yaguna

Dark matter particles annihilating into Standard Model fermions may be able to explain the recent observation of a gamma-ray excess in the direction of the Galactic Center. Recently, a hidden photon model has been proposed to explain this…

High Energy Physics - Phenomenology · Physics 2015-06-04 Samuel D. McDermott

Dark matter annihilation into charged particles is necessarily accompanied by gamma rays, produced via radiative corrections. Internal bremsstrahlung from the final state particles can produce hard gamma rays up to the dark matter mass,…

Astrophysics · Physics 2010-02-01 Nicole F. Bell , Thomas D. Jacques
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