Related papers: Axion effects on gamma-ray spectral irregularities…
In this work, we investigate the axion-like particle (ALP)-photon oscillation effect in the spectra of the blazar Markarian 421 (Mrk 421) using 4.5 years of the Astrophysical Radiation with Ground-based Observatory at YangBaJing (ARGO-YBJ)…
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,…
Axion-like particles (ALPs) are hypothetical particles and compelling candidates for cold dark matter. Their existence could be probed through their conversions into photons in the presence of magnetic fields. In this work, we explore the…
Decaying axion-like particles (ALP) with masses in the eV range which might occupy dark matter halos of the Milky Way and other galaxies produce a characteristic "bump" feature in the spectrum of extragalactic background light (EBL). This…
In this work, we re-analyze the Fermi-LAT observation of NGC 1275 to search for axion-like particle (ALP) effects and constrain ALP parameters. Instead of fitting the observed spectrum with ALP models, we adopt an alternative method for the…
Well-motivated extensions of the standard model predict ultra-light and fundamental pseudo-scalar particles (e.g., axions or axion-like particles: ALPs). Similarly to the Primakoff-effect for axions, ALPs can mix with photons and…
In many approaches to describe physics beyond the standard model, light Nambu-Goldstone bosons (named axion-like particles or ALPS for their similarity with the axion) are predicted to exist. For ALPs with a mass of neV, photon-ALPs…
Very-high-energy (VHE; $E \gtrsim 100$ GeV) gamma rays are expected to experience strong attenuation during cosmological propagation due to electron-positron pair production on the extragalactic background light (EBL). Recent observations…
The detection by the LHAASO Collaboration of the gamma-ray burst GRB 221009A at redshift $z = 0.151$ with energies up to $(13-18) \, \rm TeV$ challenges conventional physics. Photons emitted with energies above $10 \, \rm TeV$ at this…
At the beginning of 2020, MAGIC reported a very-high-energy (VHE) flaring activity from the FSRQ QSO B1420+326. It is now the fourth known most distant blazar (z=0.682) with an observed VHE gamma-ray emission. In this work, we investigate…
We report detection of a line-like feature in the $\gamma$-ray spectrum of the blazar B0516$-$621, for which the data obtained with the Large Area Telescope onboard {\it Fermi Gamma-Ray Space Telescope (Fermi)} are analyzed. The feature is…
We report on the search for spectral irregularities induced by oscillations between photons and axionlike-particles (ALPs) in the $\gamma$-ray spectrum of NGC 1275, the central galaxy of the Perseus cluster. Using six years of Fermi Large…
Axion-Like-Particles (ALPs) are hypothetical pseudo-scalar particles actively searched as light dark matter candidates. The coupling of ALPs to photons can give rise to distinctive spectral features in the observed gamma-ray spectrum of…
The extragalactic background light (EBL) plays a crucial role in the propagation of high-energy particles throughout the Universe. In this work, we explore the impact of the EBL absorption effect on photon to axionlike particle (ALP)…
Axion-like particles (ALPs) and photons can quantum mechanically interconvert when propagating through magnetic fields, and ALP-photon conversion may induce oscillatory features in the spectra of astrophysical sources. We use deep (370 ks),…
Axion-like particles (ALPs) can induce localised oscillatory modulations in the spectra of photon sources passing through astrophysical magnetic fields. Ultra-deep Chandra observations of the Perseus cluster contain over $5 \times 10^5$…
The conversion between photons and axionlike particles (ALPs) in the Milky Way magnetic field could result in the detectable oscillation phenomena in $\gamma$-ray spectra of Galactic sources. In this work, the GeV (Fermi-LAT) and TeV…
High energy photons originating from the Galactic Center (GC) region have the potential to undergo significant photon-axion-like particle (ALP) oscillation effects, primarily induced by the presence of intense magnetic fields in this…
Axionlike-particles (ALPs) are one promising type of dark matter candidate particle that may generate detectable effects on $\gamma$-ray spectra other than the canonical weakly interacting massive particles. In this work we search for such…
The mixing of photons with axion-like particles (ALPs) in the large-scale magnetic field $B$ changes the polarization angle of a linearly polarized photon beam from active galactic nuclei in radio galaxies as it propagates over cosmological…