Mangano 2007 GRB 060614的详细观测结果

主要内容:
多波段：伽玛，X，UV，optic，and spectrum。

精彩摘抄:


文章信息:
Swift observations of GRB 060614: an anomalous burst with a well behaved afterglow

Authors: V. Mangano, S.T. Holland, D. Malesani, E. Troja, G. Chincarini, B. Zhang, V. La Parola, P.J. Brown, D.N. Burrows, S. Campana, M. Capalbi, G. Cusumano, M. Della Valle, N. Gehrels, P. Giommi, D. Grupe, C. Guidorzi, T. Mineo, A. Moretti, J.P. Osborne, S.B. Pandey, M. Perri, P. Romano, P.W.A. Roming, G. Tagliaferri

(Submitted on 17 Apr 2007)

Abstract: GRB 060614 is a remarkable GRB observed by Swift with puzzling properties, which challenge current progenitor models. The lack of any bright SN down to very strict limits and the vanishing spectral lags are typical of short GRBs, strikingly at odds with the long (102s) duration of this event. Here we present spectral and temporal analysis of the Swift observations. We show that the burst presents standard optical, UV and X-ray afterglows. An achromatic break is observed simultaneously in optical and X-rays, at a time consistent with the break in the R-band light curve measured by the VLT. The achromatic behaviour and the consistent post-break decay slopes make GRB 060614 one of the best examples of a jet break for a Swift burst. The optical, UV and X-rays afterglow light curves have also an earlier break at ~30 ks. In the optical, there is strong spectral evolution around this break, suggesting the passage of a break frequency through the optical/UV band. The very blue spectrum at early times and the trend in the light curves (rising at low frequencies, and decaying at higher energies) suggest this may be the injection frequency. The early X-ray light curve is well interpreted as the X-ray counterpart of the burst extended emission. Spectral analysis of BAT/XRT data in the 80s overlap time show that the Ep of the burst has decreased to as low as 8keV at the beginning of the XRT observation. The Ep continues to decrease through the XRT energy band and exits it at about 500s after the trigger. The average Ep of the burst is likely <>

Comments:

20 pages, 9 figures, 8 tables. Abstract shortened for posting on astro-ph. Accepted for publication by A&A

Subjects:

Astrophysics (astro-ph)

Cite as:

arXiv:0704.2235v1 [astro-ph]