Presentation 1 : Oral
Observability of the Compton scattered radiation of Gamma-Ray Bursts (PCHE)
Allard, D. & Parizot, E.
The intense gamma-ray emission from GRBs lasts for 100 seconds at most. However, the emitted photons can be Compton scattered by ambient electrons in the interstellar medium, and be visible long after the explosion. We calculate the Compton scattered flux of gamma-rays from a Galactic GRB, and show that it would be observable from Earth for as much as several thousands of years, with a high gamma-ray flux. We also calculate the light curve and the shape of the emitting region at a given time after explosion, for various values of the source parameters (location, beaming angle, etc.). Resulting constraints on the last GRB event in our Galaxy and on the various GRB models are discussed.