Related papers: Seeking dark matter with $\gamma$-ray attenuation
... A strict lower-limit flux for the evolving extragalactic background light (and in particular the cosmic infrared background) has been calculated up to redshift of 5. The computed flux is below the existing upper limits from direct…
Bounds are derived on the axion-like particle (ALP) to two-photon coupling in the mass range $2.65-5.27$ eV. The bounds are obtained by searching for the signal from ALP decay in the Multi Unit Spectroscopic Explorer (MUSE) observations of…
Nearby clusters and groups of galaxies are potentially bright sources of high-energy gamma-ray emission resulting from the pair-annihilation of dark matter particles. However, no significant gamma-ray emission has been detected so far from…
Very high energy (VHE, E > 30 GeV) gamma-rays are absorbed via interaction with low-energy photons from the extragalactic background light (EBL) if the involved photon energies are above the threshold for electron-positron pair creation.…
The extragalactic background light (EBL) is the aggregate of all optical and infrared emissions from thermal processes since the cosmic dark ages. While the integrated light of galaxies is expected to be the main contribution to the EBL,…
Various theoretical models predict the existence of extended $\gamma$-ray halo around normal galaxies that could be produced by interactions of cosmic rays with the circumgalactic medium or by annihilation or decay of hypothetical dark…
The flux of electron and positron cosmic rays measured by the space-based experiments PAMELA, AMS-02, CALET, DAMPE and Fermi-LAT shows an unexpected behaviour at high energies, in comparison with expectations from standard astrophysical…
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…
We explore the potential of an artificial neural network (ANN) based method intelligence to probe the propagation of cosmic $\gamma$-ray photons in the extragalactic Universe. The journey of $\gamma$-rays emitted from a distant source like…
Background radiation fields pervade the Universe, and above a certain energy any $\gamma$-ray flux emitted by an extragalactic source should be attenuated due to $e^+e^-$ pair production. The opacity could be alleviated if photons…
We combine wide and deep galaxy number-count data from GAMA, COSMOS/G10, HST ERS, HST UVUDF and various near-, mid- and far- IR datasets from ESO, Spitzer and Herschel. The combined data range from the far-UV (0.15microns) to far-IR…
We study cross correlations between line intensity and weak lensing maps to search for axion-like particles (ALPs). Radiative decay of eV-mass ALPs can contribute to cosmic background emissions at optical and infrared wavelengths. Line…
The first measurements from the CIBER experiment of extragalactic background light (EBL) in near-infrared (NIR) band exhibit a higher intensity than those inferred through $\gamma$-ray observations. Recent theoretical-EBL intensities are…
Gamma-ray telescopes have reported some surprising observations of multi-TeV photons from distant active galactic nuclei (AGN), which show no significant attenuation due to pair production on either the extragalactic background light (EBL),…
Gamma-ray searches for new physics such as dark matter are often driven by investigating the composition of the extragalactic gamma-ray background (EGB). Classic approaches to EGB decomposition manifest in resolving individual point sources…
The detailed origin of the diffuse gamma-ray background is still unknown. However, the contribution of unresolved sources is expected to induce small-scale anisotropies in this emission, which may provide a way to identify and constrain the…
We propose a novel mechanism enabling us to have a continuum bump as a signature of gamma-ray excess in indirect detection experiments of dark matter (DM), postulating a generic dark sector having (at least) two DM candidates. With the…
Recent observations of blazars at high energy (HE, 0.1-100 GeV) and very high energy (VHE, >0.1 TeV) have provided important constraints on the intensity and spectrum of the diffuse Extragalactic Background Light (EBL), shedding light on…
We have performed an analysis of the diffuse gamma-ray emission with the Fermi Large Area Telescope in the Milky Way Halo region searching for a signal from dark matter annihilation or decay. In the absence of a robust dark matter signal,…
We discuss how measurements of the absorption of gamma-rays from GeV to TeV energies via pair production on the extragalactic background light (EBL) can probe important issues in galaxy formation. Semi-analytic models (SAMs) of galaxy…