An external-shock model for GRB afterglow 130427A

Дата и время публикации : 2013-11-22T20:15:14Z

Авторы публикации и институты :
A. Panaitescu
W. T. Vestrand
P. Wozniak

Ссылка на журнал-издание: Ссылка на журнал-издание не найдена
Коментарии к cтатье: 7 pages, MNRAS, in press
Первичная категория: astro-ph.HE

Все категории : astro-ph.HE

Краткий обзор статьи: The complex multiwavelength emission of GRB afterglow 130427A (monitored in the radio up to 10 days, in the optical and X-ray until 50 days, and at GeV energies until 1 day) can be accounted for by a hybrid reverse-forward shock synchrotron model, with inverse-Compton emerging only above a few GeV. The high ratio of the early optical to late radio flux requires that the ambient medium is a wind and that the forward-shock synchrotron spectrum peaks in the optical at about 10 ks. The latter has two consequences: the wind must be very tenuous and the optical emission before 10 ks must arise from the reverse-shock, as suggested also by the bright optical flash that Raptor has monitored during the prompt emission phase (<100 s). The VLA radio emission is from the reverse-shock, the Swift X-ray emission is mostly from the forward-shock, but the both shocks give comparable contributions to the Fermi GeV emission. The weak wind implies a large blast-wave radius (8 t_{day}^{1/2} pc), which requires a very tenuous circumstellar medium, suggesting that the massive stellar progenitor of GRB 130427A resided in a super-bubble.

Category: Physics