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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…

High Energy Astrophysical Phenomena · Physics 2026-03-13 Cervane Grimaud , Denys Malyshev , Emmanuel Moulin

Hypothetical axion-like particles (ALPs) are of interest because of their potential to act as dark matter or to reveal information about yet undiscovered fundamental constituents of matter. Such particles can be created when photons…

High Energy Astrophysical Phenomena · Physics 2025-08-19 Denys Malyshev , Lidiia Zadorozhna , Yuriy Bidasyuk , Andrea Santangelo , Oleg Ruchayskiy

Axion-like particles (ALPs) provide a compelling avenue for exploring physics beyond the Standard Model. In astrophysical magnetized plasmas an ALP-photon coupling $g_{a\gamma}$ induces energy-dependent oscillations in the photon survival…

High Energy Astrophysical Phenomena · Physics 2025-07-30 Yu Zhou , Jiejia Liu , Volodymyr Takhistov , Kazuhisa Mitsuda

Axion like particles (ALPs) are fundamental pseudo scalar particles with properties similar to Axions which are a well-known extension of the standard model to solve the strong CP problem in Quantum Chromodynamics. ALPs can oscillate into…

High Energy Astrophysical Phenomena · Physics 2017-10-30 Jhilik Majumdar , Francesca Calore , Dieter Horns

Axion Like Particles (ALPs) are predicted to couple with photons in the presence of magnetic fields. This effect may lead to a significant change in the observed spectra of gamma-ray sources such as AGNs. Here we carry out a detailed study…

Cosmology and Nongalactic Astrophysics · Physics 2009-08-31 M. A. Sanchez-Conde , D. Paneque , E. Bloom , F. Prada , A. Dominguez

Axion Like Particles (ALPs), postulated to solve the strong-CP problem, are predicted to couple with photons in the presence of magnetic fields, which may lead to a significant change in the observed spectra of gamma-ray sources such as…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-04 Miguel A. Sanchez-Conde

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 $5 \times 10^5$…

High Energy Astrophysical Phenomena · Physics 2017-10-04 Marcus Berg , Joseph P. Conlon , Francesca Day , Nicholas Jennings , Sven Krippendorf , Andrew J. Powell , Markus Rummel

X-ray observations of bright AGNs in or behind galaxy clusters offer unique capabilities to constrain axion-like particles (ALPs). Existing analysis technique rely on measurements of the global goodness-of-fit. We develop a new analysis…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-30 Joseph P. Conlon , Markus Rummel

Photons may convert to axion-like particles (ALPs) in external magnetic fields. Under certain conditions, this effect should result in irregular features in observed spectra of astrophysical sources. Lack of such irregularities in…

High Energy Astrophysical Phenomena · Physics 2020-01-30 Maxim Libanov , Sergey Troitsky

The growing interest in axion-like particles (ALPs) stems from the fact that they provide successful theoretical explanations of physics phenomena, from the anomaly of the CP-symmetry conservation in strong interactions to the observation…

High Energy Astrophysical Phenomena · Physics 2021-06-08 Ivana Batković , Alessandro De Angelis , Michele Doro , Marina Manganaro

Axion Like Particles (ALPs), postulated to solve the strong-CP problem, are predicted to couple with photons in the presence of magnetic fields, which may lead to a significant change in the observed spectra of gamma-ray sources such as…

Cosmology and Nongalactic Astrophysics · Physics 2010-01-13 Miguel A. Sanchez-Conde , David Paneque , Elliott D. Bloom , Francisco Prada , Alberto Dominguez

Axionlike particles (ALPs) are a common prediction of theories beyond the Standard Model of particle physics that could explain the entirety of the cold dark matter. These particles could be detected through their mixing with photons in…

High Energy Astrophysical Phenomena · Physics 2019-08-14 Manuel Meyer

Axion-like particles (ALPs) are predicted in some well-motivated theories beyond the Standard Model. The TeV gamma-rays from active galactic nuclei (AGN) suffer attenuation by the pair production interactions with the cosmic background…

High Energy Astrophysical Phenomena · Physics 2021-10-11 Guangbo Long , Siyu Chen , Shuo Xu , Hong-Hao Zhang

Axion-like particles (ALPs) are a common prediction of certain theories beyond the Standard Model and couple to photons in the presence of external magnetic fields. As a consequence, photon-ALP conversions could lead to an enhancement of…

High Energy Astrophysical Phenomena · Physics 2014-12-09 Manuel Meyer

A key feature of active galactic nuclei (AGN) is their variability across all wavelengths. Typically, AGN vary by a few tenths of a magnitude or more over periods lasting from hours to years. By contrast, extreme variability of AGN -- large…

High Energy Astrophysical Phenomena · Physics 2024-03-12 Summer A. J. McLaughlin , James R. Mullaney , Stuart P. Littlefair

Axion-like particles (ALPs) belong to a class of new pseudoscalar particles that generically couple to photons, opening the possibility of oscillations from photons into ALPs in an external magnetic field. Having witnessed the turbulence of…

High Energy Astrophysical Phenomena · Physics 2013-11-14 Denis Wouters , Pierre Brun

Burrage, Davis, and Shaw recently suggested exploiting the correlations between high and low energy luminosities of astrophysical objects to probe possible mixing between photons and axion-like particles (ALP) in magnetic field regions.…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-21 Guido Walter Pettinari , Robert Crittenden

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),…

High Energy Physics - Phenomenology · Physics 2017-12-27 M. C. David Marsh , Helen R. Russell , Andrew C. Fabian , Brian R. McNamara , Paul Nulsen , Christopher S. Reynolds

Axions or more generally axion-like particles (ALPs) are pseudo-scalar particles predicted by many extensions of the Standard Model of particle physics (SM) and considered as highly viable candidates for dark matter (DM) in the universe. If…

High Energy Astrophysical Phenomena · Physics 2019-11-25 Ahmed Ayad , Geoff Beck

We propose a new method to search for axion-like particles (ALPs) based on the gamma-rays produced concomitant with high-energy astrophysical neutrinos. The existence of high-energy neutrinos implies production of gamma-rays in the same…

High Energy Physics - Phenomenology · Physics 2017-12-07 Hendrik Vogel , Ranjan Laha , Manuel Meyer
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