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Related papers: The cosmic optical background excess, dark matter,…

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Axions or axion-like particles (ALPs) are well-motivated dark matter (DM) candidates whose coupling to photons induces periodic oscillations in the polarization angle of astrophysical light. This work reports the first search for such a…

High Energy Astrophysical Phenomena · Physics 2025-11-11 Qiu-Ju Huang , Bao Wang , Jun-Jie Wei , Xue-Feng Wu

The data collected by ATIC, PPB-BETS, FERMI-LAT and HESS all indicate that there is an electron/positron excess in the cosmic ray energy spectrum above $\sim$ 100 GeV, although different instrumental teams do not agree on the detailed…

High Energy Astrophysical Phenomena · Physics 2013-01-18 Yi-Zhong Fan , Bing Zhang , Jin Chang

We show that decaying axino dark matter with R-parity violation can explain the observed excess of the 130GeV gamma-ray line from the Galactic center in the Fermi data. The branching fraction of the axino decay into monochromatic photons…

High Energy Physics - Phenomenology · Physics 2013-03-28 Motoi Endo , Koichi Hamaguchi , Seng Pei Liew , Kyohei Mukaida , Kazunori Nakayama

Dark matter (DM) is a new type of invisible matter introduced to explain various features of recent astrophysical observations, including galaxy rotation curves and other fundamental characteristics of our universe. DM may couple to…

High Energy Physics - Experiment · Physics 2025-06-24 Vindhyawasini Prasad

Exclusion zones in the cross-correlations between critical points (peak-void, peak-wall, filament-wall, filament-void) of the density field define quasi-standard rulers that can be used to constrain dark matter and dark energy cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-19 Junsup Shim , Christophe Pichon , Dmitri Pogosyan , Stephen Appleby , Corentin Cadiou , Juhan Kim , Katarina Kraljic , Changbom Park

We derive constraints on dark matter (DM) annihilation cross section and decay lifetime from cross-correlation analyses of the data from Fermi-LAT and weak lensing surveys that cover a wide area of $\sim660$ squared degrees in total. We…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-29 Masato Shirasaki , Oscar Macias , Shunsaku Horiuchi , Satoshi Shirai , Naoki Yoshida

Line-Intensity Mapping is an emerging technique which promises new insights into the evolution of the Universe, from star formation at low redshifts to the epoch of reionization and cosmic dawn. It measures the integrated emission of atomic…

The Standard Model of particle physics can be extended to include sterile (right-handed) neutrinos or axions to solve the dark matter problem. Depending upon the mixing angle between active and sterile neutrinos, the latter have the…

High Energy Astrophysical Phenomena · Physics 2017-06-28 A. Gewering-Peine , D. Horns , J. H. M. M. Schmitt

Recently, a spatially extended excess of gamma rays collected by the Fermi-LAT from the inner region of the Milky Way has been detected by different groups and with increasingly sophisticated techniques. Yet, any final conclusion about the…

High Energy Astrophysical Phenomena · Physics 2015-02-11 Francesca Calore , Ilias Cholis , Christoph Weniger

The relative brightnesses of strongly lensed quasar images, called flux ratios, respond to perturbations from low-mass dark matter halos, enabling tests of dark matter models. The quasar narrow-line region (NLR) is ideal for flux-ratio…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-27 Maria F. Perez Mendoza , Anna M. Nierenberg , Vardha N. Bennert

The excess of cosmic-ray electron and positron fluxes measured by the PAMELA satellite and ATIC balloon experiments may be interpreted as the signals of the dark matter annihilation or decay into leptons. In this letter we show that the…

High Energy Physics - Phenomenology · Physics 2010-04-30 Junji Hisano , Masahiro Kawasaki , Kazunori Kohri , Kazunori Nakayama

Primordial decays of string theory moduli at z \sim 10^{12} naturally generate a dark radiation Cosmic Axion Background (CAB) with 0.1 - 1 keV energies. This CAB can be detected through axion-photon conversion in astrophysical magnetic…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-26 Joseph P. Conlon , M. C. David Marsh

Fermi measurements of the high-latitude gamma-ray background strongly constrain a decaying-dark-matter origin for the 1--100 GeV Galactic positron anomaly measured with PAMELA. Inverse-Compton scattering of the microwave background by the…

High Energy Astrophysical Phenomena · Physics 2015-05-14 Martin Pohl , David Eichler

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 study the strong gravitational lensing system number 5 identified by the CASSOWARY survey. In this system, a source at redshift 1.069 is lensed into four detected images by two early-type galaxies at redshift 0.388. The observed…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 C. Grillo , L. Christensen

Recently, indications for an emission line at 3.55 keV have been found in the combined spectra of a large number of galaxy clusters and also in Andromeda. This line could not be identified with any known spectral line. It is tempting to…

High Energy Physics - Phenomenology · Physics 2014-05-14 Joerg Jaeckel , Javier Redondo , Andreas Ringwald

Galaxy clusters are dominated by dark matter, and may have a larger proportion of surviving substructure than, e.g, field galaxies. Due to the presence of galaxy clusters in relative proximity and their high dark matter content, they are…

Cosmology and Nongalactic Astrophysics · Physics 2016-07-01 Douglas Quincy Adams , Lars Bergstrom , Douglas Spolyar

Theoretical arguments predict that the distribution of cold dark matter in spiral galaxies has peaks in velocity space associated with non-thermalized flows of dark matter particles. We searched for the corresponding peaks in the spectrum…

Several experiments have reported regions in the TeV sky with an excess of cosmic rays. Here we consider the possibility that the excess cosmic rays are coming from dark matter annihilation in nearby subhalos. We provide motivation for dark…

High Energy Astrophysical Phenomena · Physics 2013-07-25 J. Patrick Harding

A portion of light scalar dark matter, especially axions, may organize into gravitationally bound clumps (stars) and be present in large number in the galaxy today. It is therefore of utmost interest to determine if there are novel…

High Energy Physics - Phenomenology · Physics 2020-08-03 Mark P. Hertzberg , Yao Li , Enrico D. Schiappacasse