English
Related papers

Related papers: The Isotropic Radio Background and Annihilating Da…

200 papers

Observations of the extragalactic radio background have uncovered a significant isotropic emission across multiple frequencies spanning from 22 MHz to 10 GHz. The intensity of this non-thermal emission component significantly exceeds the…

High Energy Astrophysical Phenomena · Physics 2016-07-05 Ke Fang , Tim Linden

We calculate intensity and angular power spectrum of the cosmological background of synchrotron emission from cold dark matter annihilations into electron positron pairs. We compare this background with intensity and anisotropy of…

Astrophysics · Physics 2011-07-13 Le Zhang , Guenter Sigl

Recent measurements by the ARCADE2 experiment unambiguously show an excess in the isotropic radio background at frequencies below the GHz scale. We argue that this excess may be a natural consequence of the interaction of visible and dark…

Cosmology and Nongalactic Astrophysics · Physics 2014-04-25 Kyle Lawson , Ariel R. Zhitnitsky

The ARCADE 2 Collaboration has recently measured an isotropic radio emission which is significantly brighter than the expected contributions from known extra-galactic sources. The simplest explanation of such excess involves a "new"…

High Energy Physics - Phenomenology · Physics 2012-01-10 N. Fornengo , R. Lineros , M. Regis , M. Taoso

The ultracompact minihalos could be formed during the earlier epoch of the universe. The dark matter annihilation within them is very strong due to the steep density profile, $\rho \sim r^{-2.25}$. The high energy electrons and positrons…

High Energy Astrophysical Phenomena · Physics 2013-05-01 Yupeng Yang , Guilin Yang , Xiaoyuan Huang , Xuelei Chen , Tan Lu , Hongshi Zong

In this paper we show that positron data from AMS seems to rule out the explanation of the ARCADE isotropic radio background excess in terms of self-annihilating dark matter. In earlier works it was found that leptonic annihilation channels…

High Energy Physics - Phenomenology · Physics 2014-12-24 Malcolm Fairbairn , Philipp Grothaus

The isotropic gamma-ray background (IGRB), measured by the Fermi Large Area Telescope, is the result of several classes of extragalactic astrophysical sources. Those sources include blazars, start-forming galaxies and radio galaxies. Also,…

High Energy Astrophysical Phenomena · Physics 2024-08-22 Ilias Cholis , Iason Krommydas

We present an extensive analysis on the determination of the isotropic radio background. We consider six different radio maps, ranging from 22 MHz to 2.3 GHz and covering a large fraction of the sky. The large scale emission is modeled as a…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Nicolao Fornengo , Roberto A. Lineros , Marco Regis , Marco Taoso

The ARCADE 2 collaboration has reported a significant excess in the isotropic radio background, whose homogeneity cannot be reconciled with clustered sources. This suggests a cosmological origin prior to structure formation. We investigate…

Cosmology and Nongalactic Astrophysics · Physics 2013-02-06 James M. Cline , Aaron C. Vincent

Analyses of measurements of the distribution of absolute brightness temperature over the radio sky have led recently to suggestions that there exists a substantial unexplained extragalactic radio background. Consequently, there have been…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Ravi Subrahmanyan , Ramanath Cowsik

The isotropic gamma-ray background arises from the contribution of unresolved sources, including members of confirmed source classes and proposed gamma-ray emitters such as the radiation induced by dark matter annihilation and decay. Clues…

Annihilation of Dark Matter usually produces together with gamma rays comparable amounts of electrons and positrons. The e+e- gyrating in the galactic magnetic field then produce secondary synchrotron radiation which thus provides an…

Astrophysics · Physics 2009-08-19 Enrico Borriello , Alessandro Cuoco , Gennaro Miele

If dark matter decays or annihilates into electrons and positrons, it can affect radiation and cosmic-ray backgrounds. We review a novel, more general analysis of constraints on decaying dark matter models, by introducing the response…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-13 Le Zhang

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

Well-motivated models of dark matter often result in a population of electrons and positrons within galaxies produced through dark matter annihilation -- usually in association with gamma rays. As they diffuse through galactic magnetic…

High Energy Physics - Phenomenology · Physics 2024-02-23 Mitchell J. Weikert , Matthew R. Buckley

The energy-dependence of the anisotropy (the anisotropy energy spectrum) of the large-scale diffuse gamma-ray background can reveal the presence of multiple source populations. Annihilating dark matter in the substructure of the Milky Way…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Brandon S. Hensley , Jennifer M. Siegal-Gaskins , Vasiliki Pavlidou

The annihilation of dark matter particles is expected to yield a broad radiation spectrum via the production of Standard Model particles in astrophysical environments. In particular, electrons and positrons from dark matter annihilation…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-14 Emma Storm , Tesla E. Jeltema , Megan Splettstoesser , Stefano Profumo

The Large Magellanic Cloud, at only 50 kpc away from us and known to be dark matter dominated, is clearly an interesting place where to search for dark matter annihilation signals. In this paper, we estimate the synchrotron emission due to…

High Energy Astrophysical Phenomena · Physics 2011-03-16 Beatriz B. Siffert , Angelo Limone , Enrico Borriello , Giuseppe Longo , Gennaro Miele

Dark matter annihilations in the Galactic halo inject relativistic electrons and positrons which in turn generate a synchrotron radiation when interacting with the galactic magnetic field. We calculate the synchrotron flux for various dark…

Astrophysics of Galaxies · Physics 2012-01-11 N. Fornengo , R. A. Lineros , M. Regis , M. Taoso

In most of particle dark matter (DM) models, the DM candidate injects sizable fluxes of high-energy electrons and positrons through its annihilations or decays. Emitted in regions with magnetic field, they in turn give raise to a…

High Energy Physics - Phenomenology · Physics 2011-12-09 Marco Regis
‹ Prev 1 2 3 10 Next ›