GRB 170817A: a short GRB seen off-axis

doi:10.1088/1674-4527/18/4/43

CORC > 高能物理研究所 > 中国科学院高能物理研究所 > 引力波暴高能电磁对应体全天监测器（GECAM）

	GRB 170817A: a short GRB seen off-axis
	He, Xin-Bo; Thomas Tam; Pak-Hin; Shen, Rong-Feng
刊名	Research in Astronomy and Astrophysics
	2018
卷号	18 期号:4 页码:43
ISSN号	1674-4527
DOI	10.1088/1674-4527/18/4/43
文献子类	Journal article (JA)
英文摘要	The angular distribution of gamma-ray burst (GRB) jets is not yet clear. The observed luminosity of GRB 170817A is the lowest among all known short GRBs, which is best explained by the fact that our line of sight is outside of the jet opening angle, Ƞobs > Ƞj , where Ƞobs is the angle between our line of sight and the jet axis. As inferred by gravitational wave observations, as well as radio and X-ray afterglow modeling of GRB 170817A, it is likely that Ƞobs 20° C 28°. In this work, we quantitatively consider two scenarios of angular energy distribution of GRB ejecta: a top-hat jet and a structured jet with a power law index s. For the top-hat jet model, we get a large Ƞj (e.g., Ƞj > 10°), a rather high local (i.e., z < 0.01) short GRB rate 8C15×103, Gpc?3, yr?1 (estimated to be 901850 Gpc?3, yr?1 in Fong et al.) and an extremely high E peak,0 (on-axis, rest-frame) > 7.5 × 104, keV (500, keV for a typical short GRB). For the structured jet model, we use Ƞobs to give limits on s and Ȫ for typical on-axis luminosity of a short GRB (e.g., 1049 erg s?1 1051 erg s?1), and a low on-axis luminosity case (e.g., 1049 erg s?1) gives more reasonable values of s. The structured jet model is more feasible for GRB 170817A than the top-hat jet model due to the rather high local short GRB rate, and the extremely high on-axis E peak,0 almost rules out the top-hat jet model. GRB 170817A is likely a low on-axis luminosity GRB (1049 erg s?1) with a structured jet.
语种	英语
WOS记录号	WOS:000430282700007
内容类型	期刊论文
源URL	[http://ir.ihep.ac.cn/handle/311005/287852]
专题	引力波暴高能电磁对应体全天监测器（GECAM）
推荐引用方式 GB/T 7714	He, Xin-Bo,Thomas Tam,Pak-Hin,et al. GRB 170817A: a short GRB seen off-axis[J]. Research in Astronomy and Astrophysics,2018,18(4):43.
APA	He, Xin-Bo,Thomas Tam,Pak-Hin,&Shen, Rong-Feng.(2018).GRB 170817A: a short GRB seen off-axis.Research in Astronomy and Astrophysics,18(4),43.
MLA	He, Xin-Bo,et al."GRB 170817A: a short GRB seen off-axis".Research in Astronomy and Astrophysics 18.4(2018):43.