8th Heidelberg International Symposium on High-Energy Gamma-Ray Astronomy

Theoretical Modeling of the Exceptional GRB 221009A

TRANS/MWL/MM/DM

4 Sept 2024, 08:12

1m

Poster Poster hang

Speaker

Dr Luca Foffano (Istituto Nazionale di Astrofisica (INAF))

Description

The gamma-ray burst GRB 221009A stands out as an exceptional event for its intensity, spectral evolution, and duration. We investigate the early afterglow emission of this burst, especially focusing on the unique set of simultaneous GeV-TeV spectral and intensity data obtained by AGILE and LHAASO.
We present the results of a relativistic fireball model with a set of physical parameters that satisfactorily explains the first phases of the afterglow up to ${10}^4$ seconds.
Interestingly, an extension of the model to late times (up to ${10}^6$-${10}^7$ seconds) describes the late X-ray and optical spectral and intensity data in a consistent picture. Our results are important in constraining the physics of particle acceleration and evolution in GRB 221009A and can be extended to the analysis of other powerful GRBs.