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Related papers: Photon-axion conversion in Active Galactic Nuclei?

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The idea that photons can convert into axion-like particles (ALPs) $\gamma \to a$ in or around an AGN and reconvert back into photons $a \to \gamma$ in the Milky Way magnetic field has been put forward in 2008 and has recently attracted…

High Energy Astrophysical Phenomena · Physics 2015-05-20 Fabrizio Tavecchio , Marco Roncadelli , Giorgio Galanti

We examine the resonant conversion of axion-like particle (ALP) or dark photon to the electromagnetic photon in the early Universe, which takes place due to the ALP-photon-dark photon oscillations in background dark photon gauge fields. It…

High Energy Physics - Phenomenology · Physics 2020-10-28 Kiwoon Choi , Hyeonseok Seong , Seokhoon Yun

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) 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…

If axion-like particles (ALPs) exist, photons can convert to ALPs on passage through regions containing magnetic fields. The magnetised intracluster medium of large galaxy clusters provides a region that is highly efficient at ALP-photon…

High Energy Astrophysical Phenomena · Physics 2018-06-27 Linhan Chen , Joseph P. Conlon

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

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 light, neutral, pseudo-scalar bosons predicted by several extensions of the Standard Model of particle physics -- such as the String Theory -- and are supposed to interact primarily only with two photons. In…

High Energy Astrophysical Phenomena · Physics 2019-11-22 Giorgio Galanti

We study magnetic conversion of ultra-relativistic axion-like particles (ALPs) into photons in compact-star environments, focusing on the hot, transient conditions of core-collapse supernova (SN) remnants and neutron-star mergers (NSMs). We…

High Energy Physics - Phenomenology · Physics 2026-05-06 Damiano F. G. Fiorillo , Ángel Gil Muyor , Hans-Thomas Janka , Georg G. Raffelt , Edoardo Vitagliano

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

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), hypothetical extensions of the Standard Model, can convert into photons in an external magnetic field. Two recent studies~\cite{Todarello:2023ptf, Ruz:2024gkl} explored the phenomenology of ALP-photon conversion…

High Energy Physics - Phenomenology · Physics 2025-01-28 Elisa Todarello

An intriguing possibility to partially circumvent extragalactic background light (EBL) absorption in very-high-energy (VHE) observations of blazars is that photons convert into axion-like particles (ALPs) $\gamma \to a$ inside or close to a…

High Energy Astrophysical Phenomena · Physics 2014-09-11 F. Tavecchio , G. Galanti , M. Roncadelli

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

Axion-like particles (ALPs) are hypothetical entities often invoked to solve various problems in particle physics to cosmology. They are one of the most promising candidates to explain the elusive dark matter. A way to search for ALPs is…

High Energy Physics - Phenomenology · Physics 2023-08-29 Rafael Alves Batista , Cristina Viviente , Gaetano Di Marco , Miguel A. Sánchez-Conde

Very high energy gamma-ray observations of distant active galactic nuclei (AGN) generally result in higher fluxes and harder spectra than expected, resulting in some tension with the level of the extragalactic background light (EBL). If…

High Energy Astrophysical Phenomena · Physics 2015-06-19 Jonathan Harris , Paula M. Chadwick

Axion-like particles (ALPs) and photons inter-convert in the presence of a magnetic field. At keV energies in the environment of galaxy clusters, the conversion probability can become unsuppressed for light ALPs. Conversion of thermal X-ray…

High Energy Physics - Phenomenology · Physics 2016-07-06 Joseph P. Conlon , M. C. David Marsh , Andrew J. Powell

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

Various satellite-borne missions are being planned whose goal is to measure the polarization of a large number of gamma-ray bursts (GRBs). We show that the polarization pattern predicted by current models of GRB emission can be drastically…

High Energy Astrophysical Phenomena · Physics 2014-11-20 Nicola Bassan , Alessandro Mirizzi , Marco Roncadelli

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 viable candidates for dark matter (DM) in the universe. If they…

High Energy Astrophysical Phenomena · Physics 2020-05-20 Ahmed Ayad , Geoff Beck
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