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

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We propose that axion-like particles (ALPs) with a two-photon vertex, consistent with all astrophysical and laboratory bounds, may lead to a detectable signature in the spectra of high-energy gamma ray sources. This occurs as a result of…

High Energy Physics - Phenomenology · Physics 2008-11-26 Dan Hooper , Pasquale D. Serpico

Very high energy gamma-rays are expected to be absorbed by the extragalactic background light over cosmological distances via the process of electron-positron pair production. Recent observations of cosmologically distant gamma-ray emitters…

Astrophysics · Physics 2008-11-26 Melanie Simet , Dan Hooper , Pasquale D. Serpico

Axion-Like Particles (ALPs) are a generic, calculable, and well motivated extension of the Standard Model with far reaching phenomenology. ALPs that couple only to hypercharge represent one subset of such models, coupling the ALP to both…

High Energy Physics - Phenomenology · Physics 2021-09-15 Noah Steinberg , James D. Wells

Motivated by the possibility of explaining the 3.5 keV line through dark matter decaying to axion-like particles that subsequently convert to photons, we study ALP-photon conversion for sightlines passing within 50 pc of the galactic…

High Energy Physics - Phenomenology · Physics 2015-06-23 Pedro D. Alvarez , Joseph P. Conlon , Francesca V. Day , M. C. David Marsh , Markus Rummel

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), 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) are predicted by many extensions of the Standard Model (SM). When ALP mass lies in the range of MeV to GeV, the cosmology and astrophysics will be largely irrelevant. In this work, we investigate such light ALPs…

High Energy Physics - Phenomenology · Physics 2021-12-01 Daohan Wang , Lei Wu , Jin Min Yang , Mengchao Zhang

The detection of very high-energy neutrinos by IceCube experiment supports the existence of a comparable gamma-ray counterpart from the same cosmic accelerators. Under the likely assumption that the sources of these particles are of…

Axion-like particles (ALPs) are a broad class of pseudo-scalar bosons that generically arise from broken symmetries in extensions of the standard model. In many scenarios, ALPs can mix with photons in regions with high magnetic fields.…

High Energy Physics - Phenomenology · Physics 2022-03-10 Sunniva Jacobsen , Tim Linden , Katherine Freese

The hot interiors of massive stars in the later stages of their evolution provide an ideal place for the production of heavy axion-like particles (ALPs) with mass up to O(100 keV) range. We show that a fraction of these ALPs could stream…

High Energy Physics - Phenomenology · Physics 2024-12-31 James H. Buckley , P. S. Bhupal Dev , Francesc Ferrer , Takuya Okawa

Axion-like particles (ALPs) can decay into two photons with a rest-frame frequency given by half of the ALP mass. This implies that ultra-violet searches can be used to investigate ALPs in the multi-eV mass range. We use archival data from…

High Energy Physics - Phenomenology · Physics 2025-05-30 Elisa Todarello , Marco Regis

A future Galactic Supernova (SN) explosion can lead to a gamma-ray signal induced by ultralight Axion-Like Particles (ALPs) thermally produced in the SN core and converted into high-energy photons in the Galactic magnetic field. The…

High Energy Astrophysical Phenomena · Physics 2024-02-13 Francesca Calore , Pierluca Carenza , Christopher Eckner , Maurizio Giannotti , Giuseppe Lucente , Alessandro Mirizzi , Francesco Sivo

Several extensions of the Standard Model predict the existence of Axion-Like Particles (ALPs), very light spin-zero bosons with a two-photon coupling. ALPs can give rise to observable effects in very-high-energy astrophysics. Above roughly…

High Energy Astrophysical Phenomena · Physics 2015-06-05 Marco Roncadelli , Alessandro De Angelis , Giorgio Galanti

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

Axion-photon conversion is a prime mechanism to detect axion-like particles that share a coupling to the photon. We point out that in the vicinity of neutron stars with strong magnetic fields, magnetars, the effective photon mass receives…

High Energy Physics - Phenomenology · Physics 2023-10-10 Kyrylo Bondarenko , Alexey Boyarsky , Josef Pradler , Anastasia Sokolenko

Quiescent hard X-ray and soft gamma-ray emission from neutron stars constitute a promising frontier to explore axion-like-particles (ALPs). ALP production in the core peaks at energies of a few keV to a few hundreds of keV; subsequently,…

High Energy Physics - Phenomenology · Physics 2021-07-19 Jean-François Fortin , Huai-Ke Guo , Steven P. Harris , Elijah Sheridan , Kuver Sinha

Axion-like particles (ALPs) appear in various new physics models with spontaneous global symmetry breaking. When the ALP mass is in the range of MeV to GeV, the cosmology and astrophysics bounds are so far quite weak. In this work, we…

High Energy Physics - Phenomenology · Physics 2021-12-08 Jie Ren , Daohan Wang , Lei Wu , Jin Min Yang , Mengchao Zhang

Discoveries of very high energy (VHE) photons from distant blazars suggest that, after correction by extragalactic background light (EBL) absorption, there is a flatness or even a turn-up in their spectra at the highest energies that cannot…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 A. Dominguez , M. A. Sanchez-Conde , F. Prada

Axion-like particles (ALPs) are very light, neutral, spin zero bosons predicted by superstring theory. ALPs interact primarily with two photons and in the presence of an external magnetic field they generate photon-ALP oscillations and the…

High Energy Physics - Phenomenology · Physics 2022-04-29 Giorgio Galanti

In the presence of a background magnetic field, axions or axion-like particles (ALPs) can be resonantly converted to photons when their mass is nearly equal to the effective photon mass. In this paper, we propose a novel method to constrain…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-21 Ashu Kushwaha , Rajeev Kumar Jain