English
Related papers

Related papers: An observable electron-positron anisotropy cannot …

200 papers

High energy electrons and positrons from annihilating dark matter can imprint unique angular anisotropies on the diffuse gamma-ray flux by inverse Compton scattering off the interstellar radiation field. We develop a numerical tool to…

High Energy Astrophysical Phenomena · Physics 2011-02-10 Le Zhang , Francesco Miniati , Guenter Sigl

Recently published results from the PAMELA experiment have shown conclusive evidence for an excess of positrons at high (~ 10 - 100 GeV) energies, confirming earlier indications from HEAT and AMS-01. Such a signal is generally expected from…

Astrophysics · Physics 2009-12-15 Ilias Cholis , Douglas P. Finkbeiner , Lisa Goodenough , Neal Weiner

Precision measurements of the positron flux in cosmic ray have revealed an unexplained bump in the spectrum around $E\simeq 300\,\mathrm{GeV}$, not clearly attributable to known astrophysical processes. We propose annihilation of dark…

High Energy Physics - Phenomenology · Physics 2020-06-11 Anirban Das , Basudeb Dasgupta , Anupam Ray

The precise measurements of energy spectra of cosmic ray positrons and/or electrons by recent experiments show clear excesses above 10 GeV. Moreover, a potential sharp spectral feature was suggested by the Dark Matter Particle Explorer…

High Energy Physics - Phenomenology · Physics 2020-04-29 Lei Feng , Zhaofeng Kang , Qiang Yuan , Peng-Fei Yin , Yi-Zhong Fan

Cosmic-ray and gamma-ray observations have yielded several notable excesses that often lend themselves to explanation by various dark matter annihilation/decay models. In particular, the AMS-02 anti-proton and positron excesses have…

High Energy Astrophysical Phenomena · Physics 2019-09-04 Geoff Beck

The PAMELA and ATIC collaborations have recently reported an excess in the cosmic ray positron and electron fluxes. These lepton anomalies might be related to cold dark matter (CDM) particles annihilating within a nearby dark matter clump.…

High Energy Astrophysical Phenomena · Physics 2009-09-01 Pierre Brun , Timur Delahaye , Juerg Diemand , Stefano Profumo , Pierre Salati

Deviations from isotropy have been a key tool to identify the sources and the primary type of cosmic rays (CRs) at low energies. We argue that anisotropies due to blind regions induced by the Galactic magnetic field, the cosmological…

Astrophysics · Physics 2008-11-26 M. Kachelriess

Motivated by the anomalous positron flux recently reported by the PAMELA collaboration, we study the cosmic-ray positron produced by the pair annihilation and the decay of superparticle dark matter. We calculate the cosmic-ray positron flux…

High Energy Physics - Phenomenology · Physics 2015-05-13 Koji Ishiwata , Shigeki Matsumoto , Takeo Moroi

We present the energy spectra of the fluxes of positrons, anti-protons and photons generated by Dark Matter annihilations in our galaxy, as univocally predicted by the model of Minimal Dark Matter. Due to multi-TeV masses and to the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Marco Cirelli , Roberto Franceschini , Alessandro Strumia

The origin of an anomalous excess of high-energy (about 100 GeV and higher) positrons in cosmic rays is one of the rare problems in this field, which is proposed to be solved with dark matter (DM). Attempts to solve this problem are faced…

High Energy Astrophysical Phenomena · Physics 2023-10-12 Ramin Barak , Konstantin Belotsky , Ekaterina Shlepkina

The annihilation of dark matter (DM) particles in the Milky Way can contribute to the diffuse gamma-ray background (DGRB). Due to the presence of substructures, this emission will appear anisotropic in a predictable way. We generate…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 J. U. Lange , M. -C. Chu

Cosmic-ray positrons have long been considered a powerful probe of dark matter annihilation. In particular, myriad studies of the unexpected rise in the positron fraction have debated its dark matter or pulsar origins. In this paper, we…

High Energy Astrophysical Phenomena · Physics 2022-01-07 Isabelle John , Tim Linden

Dark matter is a popular candidate to a new source of primary-charged particles, especially positrons in cosmic rays, which are proposed to account for observable anomalies. While this hypothesis of decaying or annihilating DM is mostly…

High Energy Physics - Phenomenology · Physics 2023-11-13 Konstantin Belotsky , Maxim Solovyov

The Large Area Telescope on board the Fermi Gamma-ray Space Telescope has collected the largest ever sample of high-energy cosmic-ray electron and positron events since the beginning of its operation. Potential anisotropies in the arrival…

High Energy Astrophysical Phenomena · Physics 2017-03-06 LAT Collaboration

The excesses of the cosmic positron fraction recently measured by PAMELA and the electron spectra by ATIC, PPB-BETS, Fermi and H.E.S.S. indicate the existence of primary electron and positron sources. The possible explanations include dark…

Astrophysics · Physics 2009-09-02 Juan Zhang , Xiao-jun Bi , Jia Liu , Si-Ming Liu , Peng-fei Yin , Qiang Yuan , Shou-hua Zhu

The bulge of our Galaxy is illuminated by the 0.511 MeV gamma-ray line flux from annihilations of nonrelativistic positrons. The emission is strongly concentrated at the Galactic Center, in contrast to gamma-ray maps tracing nucleosynthesis…

Astrophysics · Physics 2008-11-26 Hasan Yuksel

This paper proposes and discusses a test of the chemical composition of ultra-high energy cosmic rays that relies on the anisotropy patterns measured as a function of energy. In particular, we show that if one records an anisotropy signal…

High Energy Astrophysical Phenomena · Physics 2009-11-13 Martin Lemoine , Eli Waxman

We discuss the possibility of identification of point-like gamma-ray sources (PGS) with small scale dark matter (DM) clumps in our Galaxy. Gamma-rays are supposed to originate from annihilation of DM particles in the clumps, where…

High Energy Astrophysical Phenomena · Physics 2014-04-09 K. M. Belotsky , A. A. Kirillov , M. Yu. Khlopov

We discuss the possibility of solving the inverse problem of the cosmic-ray electron/positron from decaying/annihilating dark matter, and show simple analytic formulae to reconstruct the source spectrum of the electron/positron from the…

High Energy Physics - Phenomenology · Physics 2009-10-02 Koichi Hamaguchi , Kouhei Nakaji , Eita Nakamura

Resonant positron annihilation on atomic electrons provides a powerful method to search for light new particles coupled to $e^+e^-$. Reliable estimates of production rates require a detailed characterization of electron momentum…

High Energy Physics - Phenomenology · Physics 2024-10-11 Fernando Arias-Aragón , Luc Darmé , Giovanni Grilli di Cortona , Enrico Nardi