A two-component jet model for the optical plateau in the afterglow of GRB 191221B

Zhu, Y.; Wang, Y.; Zhou, H.; Lipunov, V.; Buckley David, A.H.; Balanutsa, P.; Jin, Z.; Wei, D.

Авторы: Zhu Yi-Ming, Wang Yun, Zhou Hao, Lipunov Vladimir, Buckley David A.H., Balanutsa Pavel, Jin Zhi-Ping, Wei Da-Ming
Журнал: Monthly Notices of the Royal Astronomical Society
Том: 527
Номер: 2
Год издания: 2023
Издательство: Oxford Journals, Oxford University Press
Местоположение издательства: Oxford, UK, England
Первая страница: 1638
Последняя страница: 1647
DOI: 10.1093/mnras/stad3229
Аннотация: The long gamma-ray burst GRB 191221B has abundant observations in X-ray, optical and radio bands. In the literature, the observed optical light curve of GRB 191221B displays a plateau around 0.1-day, which is rather peculiar in gamma-ray bursts. Here we performed detailed analysis of the observational data from Swift/UVOT, VLT and LCO, obtained the light curve of the multi-band afterglow of GRB 191221B. By examining optical, ultraviolet, X-ray, and radio data for this event, we demonstrate that an on-axis two-component jet model can explain the observations. Our analysis suggests that the narrow component has an initial Lorentz factor of 400 and a jet opening half-angle of 1.4○, while the wide component has an initial Lorentz factor of 25 and a jet opening half-angle of 2.8○. The narrow jet dominates the early decay, whereas the wider jet causes the optical plateau and dominates late decay. According to this model, the reason for the absence of the X-ray plateau is due to the steeper spectral index of the wide component, resulting in a less significant flux contribution from the wide jet in the X-ray bands than in the optical bands. Moreover, we have explained the inconsistency in the decay indices of the UVOT and Rc-band data around 2000 seconds using reverse shock emission. https://academic.oup.com/mnras/advance-article/doi/10.1093/mnras/stad3229/7326774
Добавил в систему: Липунов Владимир Михайлович

	ИСТИНА	Войти в систему Регистрация
	ФНКЦ РР
	Главная Поиск Статистика О проекте Помощь

ИСТИНА

ФНКЦ РР

A two-component jet model for the optical plateau in the afterglow of GRB 191221Bстатья

Прикрепленные файлы