Shimmering gravitons in the gamma-ray sky

0574596 - FZÚ 2024 RIV US eng J - Článek v odborném periodiku
Ramazanov, Sabir - Samanta, Rome - Trenkler, Georg - Urban, Federico
Shimmering gravitons in the gamma-ray sky.
Journal of Cosmology and Astroparticle Physics. Roč. 2023, č. 6 (2023), č. článku 019. ISSN 1475-7516. E-ISSN 1475-7516
Grant CEP: GA MŠMT EF15_003/0000437; GA ČR(CZ) GA20-28525S
Grant ostatní: OP VVV - CoGraDS(XE) CZ.02.1.01/0.0/0.0/15_003/0000437
Institucionální podpora: RVO:68378271
Klíčová slova: gamma ray theory * gravitational wave detectors * galactic magnetic fields * dark matter theory
Obor OECD: Particles and field physics
Impakt faktor: 6.3, rok: 2022
Způsob publikování: Open access

What is the highest energy at which gravitons can be observed? We address this question by studying graviton-to-photon conversion - the inverse-Gertsenshtein effect - in the magnetic field of the Milky Way. We find that above ~ 1 PeV the effective photon mass grows large enough to quench the conversion rate. For sub-PeV energies, the induced photon flux is comparable to the sensitivity of LHAASO to a diffuse γ-ray background, but only for graviton abundances of order Ωgw h0^2 ~ 1. In the future, owing to a better understanding of γ-ray backgrounds, larger effective areas and longer observation times, sub-PeV shimmering gravitons with a realistic abundance of Ωgw h0^2 ~ 0.01 could be detected. We show how such a large abundance is achieved in a cosmologically-motivated scenario of post-recombination superheavy dark matter decay. Therefore, the sub-PeV range might be the ultimate energy frontier at which gravitons can be observed.
Trvalý link: https://hdl.handle.net/11104/0348535