GRB 091127 is a bright gamma-ray burst detected by Swift at a redshift z=0.49, and associated to SN 2009nz. We present the broadband analysis of the GRB prompt and afterglow emission and study its high-energy property in the context of the GRB/SN association. While the high luminosity of the prompt emission and standard afterglow behavior are typical of cosmological long GRBs, its low gamma-ray energy release (E <3×1049 erg), soft spectrum and unusual spectral lag connect this GRB to the class of sub-energetic bursts. We finally discuss the suppression of high-energy emission in this burst, and investigate whether this behavior could be connected with the sub-energetic nature of the explosion.
Broadband study of 091127: a sub-energetic burst at higher redshift?
GUIDORZI, Cristiano;
2012
Abstract
GRB 091127 is a bright gamma-ray burst detected by Swift at a redshift z=0.49, and associated to SN 2009nz. We present the broadband analysis of the GRB prompt and afterglow emission and study its high-energy property in the context of the GRB/SN association. While the high luminosity of the prompt emission and standard afterglow behavior are typical of cosmological long GRBs, its low gamma-ray energy release (E <3×1049 erg), soft spectrum and unusual spectral lag connect this GRB to the class of sub-energetic bursts. We finally discuss the suppression of high-energy emission in this burst, and investigate whether this behavior could be connected with the sub-energetic nature of the explosion.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.