Circular polarization in the optical afterglow of GRB 121024A

CORC > 紫金山天文台 > 中国科学院紫金山天文台 > 宇宙伽马暴、中子星及相关物理研究团组

	Circular polarization in the optical afterglow of GRB 121024A
	Wiersema, K.1; Covino, S.2; Toma, K.3,4,5; van der Horst, A. J.6; Varela, K.7; Min, M.6; Greiner, J.7; Starling, R. L. C.1; Tanvir, N. R.1; Wijers, R. A. M. J.6
刊名	NATURE
	2014-05-08
卷号	509 期号:7499 页码:201-+
ISSN号	0028-0836
英文摘要	Gamma-ray bursts (GRBs) are most probably powered by collimated relativistic outflows (jets) from accreting black holes at cosmological distances. Bright afterglows are produced when the outflow collides with the ambient medium. Afterglow polarization directly probes the magnetic properties of the jet when measured minutes after the burst, and it probes the geometric properties of the jet and the ambient medium when measured hours to days after the burst(1-5). High values of optical polarization detected minutes after the burst of GRB 120308A indicate the presence of large-scale ordered magnetic fields originating from the central engine(5) (the power source of the GRB). Theoretical models predict low degrees of linear polarization and no circular polarization at late times(6-8), when the energy in the original ejecta is quickly transferred to the ambient medium and propagates farther into the medium as a blast wave. Here we report the detection of circularly polarized light in the afterglow of GRB 121024A, measured 0.15 days after the burst. We show that the circular polarization is intrinsic to the afterglow and unlikely to be produced by dust scattering or plasma propagation effects. A possible explanation is to invoke anisotropic (rather than the commonly assumed isotropic) electron pitch-angle distributions, and we suggest that new models are required to produce the complex microphysics of realistic shocks in relativistic jets(9-11).
WOS标题词	Science & Technology
类目[WOS]	Multidisciplinary Sciences
研究领域[WOS]	Science & Technology - Other Topics
关键词[WOS]	GAMMA-RAY BURSTS ; RELATIVISTIC COLLISIONLESS SHOCKS ; MAGNETIC-FIELD STRUCTURE ; LINEAR-POLARIZATION ; LIGHT CURVES ; EMISSION ; POLARIMETRY ; DUST ; JETS ; EXTINCTION
收录类别	SCI
原文出处	10.1038/nature13237
语种	英语
WOS记录号	WOS:000335454300033
公开日期	2014-11-21
内容类型	期刊论文
源URL	[http://libir.pmo.ac.cn/handle/332002/10707]
专题	紫金山天文台_宇宙伽马暴、中子星及相关物理研究团组
作者单位	1.Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England 2.INAF Brera Astron Observ, I-23807 Merate, LC, Italy 3.Osaka Univ, Dept Earth & Space Sci, Toyonaka, Osaka 5600043, Japan 4.Tohoku Univ, Astron Inst, Sendai, Miyagi 9808578, Japan 5.Tohoku Univ, Frontier Res Inst Interdisciplinary Sci, Sendai, Miyagi 9808578, Japan 6.Univ Amsterdam, Astron Inst Anton Pannekoek, NL-1090 SJ Amsterdam, Netherlands 7.Max Planck Inst Extraterr Phys, D-85748 Garching, Germany 8.Curtin Univ, Int Ctr Radio Astron Res, Perth, WA 6845, Australia 9.Chinese Acad Sci, Purple Mt Observ, Key Lab Dark Matter & Space Astron, Nanjing 210008, Peoples R China 10.Univ Copenhagen, Niels Bohr Inst, Dark Cosmol Ctr, DK-2100 Copenhagen, Denmark
推荐引用方式 GB/T 7714	Wiersema, K.,Covino, S.,Toma, K.,et al. Circular polarization in the optical afterglow of GRB 121024A[J]. NATURE,2014,509(7499):201-+.
APA	Wiersema, K..,Covino, S..,Toma, K..,van der Horst, A. J..,Varela, K..,...&Willingale, R..(2014).Circular polarization in the optical afterglow of GRB 121024A.NATURE,509(7499),201-+.
MLA	Wiersema, K.,et al."Circular polarization in the optical afterglow of GRB 121024A".NATURE 509.7499(2014):201-+.