Guidorzi 2007 GRB 070311的多波段观测

主要内容:
给出了GRB 070311的多波段观测结果

精彩摘抄:

对数图上的多波段光变

光学波段的peak和伽玛射线的位置不同，有延后。

文章信息:

arXiv:0708.1383 [ps, pdf, other]

Title: GRB 070311: a direct link between the prompt emission and the afterglow

Authors: C. Guidorzi, S.D. Vergani, S. Sazonov, S. Covino, D. Malesani, S. Molkov, E. Palazzi, P. Romano, S. Campana, G. Chincarini, D. Fugazza, A. Moretti, G. Tagliaferri, A. Llorente, J. Gorosabel, L.A. Antonelli, M. Capalbi, G. Cusumano, P. D'Avanzo, V. Mangano, N. Masetti, E. Meurs, T. Mineo, E. Molinari, D.C. Morris, L. Nicastro, K.L. Page, M. Perri, B. Sbarufatti, G. Stratta, R. Sunyaev, E. Troja, F.M. Zerbi

Comments: 14 pages, 11 figures, 4 tables, accepted to A&A

Subjects: Astrophysics (astro-ph)

We present prompt gamma-ray, early NIR/optical, late optical and X-ray observations of the peculiar GRB 070311 discovered by INTEGRAL, in order to gain clues on the mechanisms responsible for the prompt gamma-ray pulse as well as for the early and late multi-band afterglow of GRB 070311. We fitted with empirical functions the gamma-ray and optical light curves and scaled the result to the late time X-rays. The H-band light curve taken by REM shows two pulses peaking 80 and 140 s after the peak of the gamma-ray burst and possibly accompanied by a faint gamma-ray tail. Remarkably, the late optical and X-ray afterglow underwent a major rebrightening between 3x10^4 and 2x10^5 s after the burst with an X-ray fluence comparable with that of the prompt emission extrapolated in the same band. Notably, the time profile of the late rebrightening can be described as the combination of a time-rescaled version of the prompt gamma-ray pulse and an underlying power law. This result supports a common origin for both prompt and late X-ray/optical afterglow rebrightening of GRB 070311 within the external shock scenario. The main fireball would be responsible for the prompt emission, while a second shell would produce the rebrightening when impacting the leading blastwave in a refreshed shock (abridged).