English
Related papers

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

200 papers

Oscillations from high energy photons into light pseudoscalar particles in an external magnetic field are expected to occur in some extensions of the standard model. It is usually assumed that those axionlike particles (ALPs) could produce…

High Energy Astrophysical Phenomena · Physics 2012-09-13 Denis Wouters , Pierre Brun

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…

High Energy Astrophysical Phenomena · Physics 2022-06-22 Damiano F. G. Fiorillo , Fabio Iocco

The existence of an axion-like particle (ALP) would induce anomalous scattering of light by light. This process can be probed at the Large Hadron Collider in central exclusive production of photon pairs in proton-proton collisions by…

High Energy Physics - Phenomenology · Physics 2018-08-01 Cristian Baldenegro , Sylvain Fichet , Gero von Gersdorff , Christophe Royon

Axion-like-particles (ALPs) emitted from the core of a magnetar can convert to photons in its magnetosphere. The resulting photon flux is sensitive to the product of $(i)$ the ALP-nucleon coupling $G_{an}$ which controls the production…

High Energy Astrophysical Phenomena · Physics 2021-01-20 Sheridan J. Lloyd , Paula M. Chadwick , Anthony M. Brown , Huai-ke Guo , Kuver Sinha

We derive updated cosmological bounds on light axion-like particles (ALPs) coupled to leptons or photons, using a full phase-space treatment of their production from the primordial thermal plasma. The ALP phase-space distribution, obtained…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-12 Nicola Barbieri , Luca Caloni , Martina Gerbino , Massimiliano Lattanzi , Luca Visinelli

We have incorporated the description of the X-ray properties of Active Galactic Nuclei (AGNs) into a semi-analytic model of galaxy formation, adopting physically motivated scaling laws for accretion triggered by galaxy encounters. Our model…

Astrophysics · Physics 2009-11-10 N. Menci , F. Fiore , G. C. Perola , A. Cavaliere

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…

High Energy Physics - Phenomenology · Physics 2018-05-02 Jhilik Majumdar , Francesca Calore , Dieter Horns

We present a novel approach to investigating axions and axion-like particles (ALPs) by studying their potential conversion into X-rays within the Sun's atmospheric magnetic field. Utilizing high-sensitivity data from the Nuclear…

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…

High Energy Astrophysical Phenomena · Physics 2014-08-19 Rebecca Reesman , T. P. Walker

Axionlike particles (ALPs) can be produced in the Sun, and are considered viable candidates for the cosmological dark matter (DM). It can decay into two photons or interact with matter. We identify new inelastic channels of inverse…

High Energy Physics - Phenomenology · Physics 2023-08-29 C. -P. Wu , C. -P. Liu , Greeshma C. , L. Singh , J. -W. Chen , H. -C. Chi , M. K. Pandey , H. T. Wong

Active Galactic Nuclei (AGN) produce a dominant fraction (~80%) of the Soft X-ray background (SXB) at photon energies 0.5<E<2 keV. If dust pervaded throughout the intergalactic medium, its scattering opacity would have produced diffuse…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Mark Dijkstra , Abraham Loeb

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…

High Energy Physics - Phenomenology · Physics 2017-11-27 Jhilik Majumdar , Francesca Calore , Dieter Horns

Experimental searches for Axion-Like Particles (ALPs) which couple to the electroweak bosons span over a wide range of ALP masses, from MeV searches at beam-dump experiments, to TeV searches at the LHC. Here we examine an interesting range…

High Energy Physics - Phenomenology · Physics 2021-08-27 Noah Steinberg

It was recently pointed out that very energetic subclasses of supernovae (SNe), like hypernovae and superluminous SNe, might host ultra-strong magnetic fields in their core. Such fields may catalyze the production of feebly interacting…

Due to their high magnetic fields and plasma densities, pulsars provide excellent laboratories for tests of beyond Standard Model (BSM) physics. When axions or axion-like particles (ALPs) approach closely enough to pulsars, they can be…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-29 Anirudh Prabhu , Nicholas M. Rapidis

Active Galactic Nuclei (AGN) are known to show flux variability over all observable timescales and across the entire electromagnetic spectrum. Over the past decade, a growing number of sources have been observed to show dramatic flux and…

Astrophysics of Galaxies · Physics 2022-11-11 Claudio Ricci , Benny Trakhtenbrot

The cumulative emission of Axion-Like Particles (ALPs) from all past core-collapse supernovae (SNe) would lead to a diffuse flux with energies ${\mathcal O}(50)$ MeV. We use this to constrain ALPs featuring couplings to photons and to…

High Energy Physics - Phenomenology · Physics 2020-12-03 Francesca Calore , Pierluca Carenza , Maurizio Giannotti , Joerg Jaeckel , Alessandro Mirizzi

Limits on spin-0 axion-like-particles (ALPs) coupling to photons are reinterpreted as constraints on massive spin-2 graviton-like-particles (GLPs) with universal coupling $\alpha_\text{G}/M_\text{P}$ (where $M_\text{P}$ is the reduced…

High Energy Physics - Phenomenology · Physics 2026-05-05 Jordan Gué , David d'Enterria

Galaxy clusters contain large magnetic fields that make them excellent targets to search for ultralight Axion-Like Particles (ALPs). ALP-photon interconversion imprints quasi-sinusoidal oscillations on the X-ray spectra of point sources in…

High Energy Astrophysical Phenomena · Physics 2017-11-08 Nicholas Jennings

We study an axion-like particle (ALP) that experiences the first-order phase transition with respect to its mass or potential minimum. This can be realized if the ALP obtains a potential from non-perturbative effects of SU($N$) gauge theory…

High Energy Physics - Phenomenology · Physics 2023-04-05 Shota Nakagawa , Fuminobu Takahashi , Masaki Yamada , Wen Yin