TY - GEN
T1 - When GRB afterglows get softer, hard components come into play
AU - Moretti, A.
AU - Margutti, R.
AU - Pasotti, F.
AU - Beardmore, A. P.
AU - Campana, S.
AU - Chincarini, G.
AU - Covino, S.
AU - Godet, O.
AU - Guidorzi, C.
AU - Osborne, J. P.
AU - Romano, P.
AU - Tagliaferri, G.
PY - 2008
Y1 - 2008
N2 - We investigated the ability of simple spectral models to describe the early afterglow emission of GRBs. We found that four spectra, belonging to the GRB060502A, GRB060729, GRB060904B, GRB061H0A prompt-afterglow transition phase, can be modeled neither by a single power-law nor by the Band model. Instead we find that the data present high-energy (>3keV, in the observer frame) statistically significant excesses with respect to these models In all four cases, the deviations can be modeled well by adding either a second power law or a blackbody component to the usual synchrotron power law spectrum. Although the data do not allow an unequivocal physical interpretation, the importance of this analysis consists in showing that a simple power-law model or a Band model is insufficient to describe the X-ray spectra of a small homogeneous sample of GRBs at the end of their prompt phase [1].
AB - We investigated the ability of simple spectral models to describe the early afterglow emission of GRBs. We found that four spectra, belonging to the GRB060502A, GRB060729, GRB060904B, GRB061H0A prompt-afterglow transition phase, can be modeled neither by a single power-law nor by the Band model. Instead we find that the data present high-energy (>3keV, in the observer frame) statistically significant excesses with respect to these models In all four cases, the deviations can be modeled well by adding either a second power law or a blackbody component to the usual synchrotron power law spectrum. Although the data do not allow an unequivocal physical interpretation, the importance of this analysis consists in showing that a simple power-law model or a Band model is insufficient to describe the X-ray spectra of a small homogeneous sample of GRBs at the end of their prompt phase [1].
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U2 - 10.1063/1.2943448
DO - 10.1063/1.2943448
M3 - Conference contribution
AN - SCOPUS:84874885578
SN - 9780735405332
T3 - AIP Conference Proceedings
SP - 216
EP - 219
BT - Gamma-Ray Bursts 2007 - Proceedings of the Santa Fe Conference
T2 - Santa Fe Conference on Gamma-Ray Bursts 2007, GRB 2007
Y2 - 5 November 2007 through 9 November 2007
ER -