GRB4 - Models for GRBs |
Speaker |
Fan, Yizhong |
Talk Title |
Interpretation and implication of the non-detection of GeV spectrum excess by Fermi $\gamma$-ray Space Telescope in most GRBs |
Abstract |
Since the launch of the Fermi Gamma-ray Space Telescope on 11 June 2008, significant detections of high energy emission have been reported only in seven Gamma-ray Bursts (GRBs) until now. In this work we show that the lack of detection of a GeV spectrum excess in almost all GRBs, though somewhat surprisingly, can be well understood within the standard internal shock model and several alternatives like the photosphere-internal shock (gradual magnetic dissipation) model and the magnetized internal shock model. The delay of the arrival of the $>100$ MeV photons from some Fermi bursts can be interpreted too. |
Talk view |
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