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arXiv · 2303.03137

Intergalactic magnetic field studies by means of $\gamma$-ray emission from GRB 190114C

Paolo Da Vela·Guillem Martí-Devesa·Francesco Gabriele Saturni·Peter Veres·Antonio Stamerra·Francesco Longo
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Abstract

The presence of delayed GeV emission after a strong transient, such as a GRB (Gamma-Ray Burst), in the VHE (Very-High Energy, $E>100$ GeV) band can be the signature of a non-zero magnetic field in the intergalactic medium. We used a synchrotron self-Compton multiwavelength model to infer an analytical description of the intrinsic VHE spectrum (corrected for absorption by the Extragalactic Background Light, EBL) of GRB$\,$190114C to predict the lightcurves and SEDs of the delayed emission with Monte Carlo simulations for different IGMF (Intergalactic Magnetic Field) configurations (strengths $B=8\times10^{-21}$ G, $10^{-20}$ G, $3\times 10^{-20}$G and correlation length $\lambda>1$ Mpc), and compared them with the Fermi-LAT (Fermi Large Area Telescope) limits computed for several exposure times. We found that Fermi LAT is not sensitive enough to constrain any IGMF strengths using GRB$\,$190114C.

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Paolo Da Vela, Guillem Martí-Devesa, Francesco Gabriele Saturni, Peter Veres, Antonio Stamerra, Francesco Longo. 2023-03-06. Intergalactic magnetic field studies by means of $\gamma$-ray emission from GRB 190114C. https://doi.org/10.1103/physrevd.107.063030

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