Related papers: First constraints on axion-like particles from Gal…
The CIBER collaboration released their first observational data of the Cosmic IR background (CIB) radiation, which has significant excesses at around the wavelength $\sim$ 1 $\mu$m compared to theoretically-inferred values. The amount of…
The production of very-high-energy (VHE, $E_{\gamma} \gtrsim 100$ GeV) gamma rays resulting from the scattering of high-energy cosmic-ray protons off axion-like particles (ALPs) populating the dark matter halo of the Milky Way is…
It has been recently claimed by two different groups that the spectral modulation observed in gamma rays from Galactic pulsars and supernova remnants can be due to conversion of photons into ultra-light axion-like-particles (ALPs) in…
The observed very high energy spectra of distant blazars are well described by secondary gamma rays produced in line-of-sight interactions of cosmic rays with background photons. In the absence of the cosmic-ray contribution, one would not…
With the breakthrough in PeV gamma-ray astronomy brought by the LHAASO experiment, the high-energy sky is getting richer than before. Lately, LHAASO Collaboration reported the observation of a gamma-ray diffuse emission with energy up to…
Galactic diffuse gamma-ray flux measured by the Tibet AS$\gamma$ experiment and the total Galactic gamma-ray flux measured by Large High Altitude Air Shower Observatory (LHAASO) are found to be consistent, within the statistical and…
Axion-like particles (ALPs) can be produced by thermal processes in a stellar interior, escape from the star and, if sufficiently light, be converted into photons in the external Galactic magnetic field. Such a process could produce a…
The IceCube Collaboration has recently reported evidence for a high-energy extraterrestrial neutrino flux. During two years of operation 28 events with energies between 30 TeV and 1.2 PeV were observed while only 10.6 events were expected…
Axion-like particles (ALP) can in principle be produced in very hot and dense astrophysical environments, escape from the extreme object where such conditions are met, and then be converted in gamma--rays in the magnetic fields intervening…
Axion-like particles (ALPs) coupled to nucleons can be efficiently produced in core-collapse supernovae (SNe) and then, if they couple to photons, convert into gamma rays in cosmic magnetic fields, generating short gamma-ray bursts. Though…
Very recently, the Tibet-AS$\gamma$ collaboration reported the detection of $\gamma$ rays from the galactic disk in the energy range of 100 TeV -- 1 PeV. Remarkably, many of these $\gamma$ rays were observed apart from known very high…
IceCube experiment has detected two neutrinos with energies beween 1-10 PeV. They might have originated from Galactic or extragalactic sources of cosmic rays. In the present work we consider hadronic interactions of the diffuse very high…
The IceCube Neutrino Observatory has detected high-energy astrophysical neutrinos in the TeV-PeV range. These neutrinos have an isotropic distribution on the sky, and therefore, likely originate from extragalactic sources. Active Galactic…
The very high energy Galactic $\gamma$-ray sky is partially opaque in the ($0.1-10$) PeV energy range. In the light of the recently detected high energy neutrino flux by IceCube, a comparable very high energy $\gamma$-ray flux is expected…
Gamma-rays from cosmological sources contain information about gamma-ray interactions. Standard model and non-standard model photon interactions along the path between the source and the observer can lead to changes in the energy or state…
We use the first observation of Betelgeuse in hard $X$-rays to perform a novel search for axion-like particles (ALPs). Betelgeuse is not expected to be a standard source of $X$-rays, but light ALPs produced in the stellar core could be…
The diffuse $\gamma$-ray spectrum at sub-PeV energy region has been measured for the first time by the Tibet-AS$\gamma$ experiment. It will shed new light on the understanding of origin and propagation of Galactic cosmic rays at very high…
High-energy photons may oscillate with axion-like particles (ALPs) when they propagate through the Milky Way's magnetic field, resulting in an alteration in the observed photon energy spectrum. The ultra-high energy gamma-ray spectra,…
We calculate the production of ultra-light axion-like particles (ALPs) in a nearby supernova progenitor. Once produced, ALPs escape from the star and a part of them is converted into photons during propagation in the Galactic magnetic…
We present a self-consistent interpretation of the of very-high-energy neutrino signal from the direction of the inner Galaxy, which is a part of the astronomical neutrino signal reported by IceCube. We demonstrate that an estimate of the…