Gamma Ray Burst GRB 221009A: two distinct hints at once at new physics

Abstract

The brightest ever observed gamma ray burst GRB 221009A at redshift $z=0.151$ was detected on October 9, 2022. Its highest energy photons have been recorded by the LHAASO collaboration up to above $12\mathrm{TeV}$, and one of the at $\mathcal{E}=251\mathrm{TeV}$ by the Carpet-2 collaboration. Very recently, the Carpet-3 collaboration has completed the data analysis, showing that the evidence of the $251\mathrm{TeV}$ photon is quite robust. Still, according to conventional physics photons with $\mathcal{E}\gtrsim 10\mathrm{TeV}$ cannot be observed owing to the absorption by the extragalactic background light (EBL). Previously it has been demonstrated that an axion-like particle (ALP) with allowed parameters ensures the observability of the LHAASO photons. Here we show that the Lorentz invariance violation allows the $\mathcal{E}=251\mathrm{TeV}$ (now around 300 TeV) Carpet photon to be detected.

Comments: 3 pages, 1 figure