Watson 2007 两个无超新星成协的长暴

主要内容:
GRBs 060505 and 060614的宿主星系的观测表面应该来自于大质量恒星的坍缩，但在很大范围内都没有看到超新星成份，说明可能还有另一种产生长伽玛暴的机制。

精彩摘抄:


文章信息:
No supernovae detected in two long-duration Gamma-Ray Bursts

Authors: D. Watson (1), J. P. U. Fynbo (1), C. C. Thöne (1), J. Sollerman (1,2) ((1) DARK, NBI, U. Copenhagen, (2) U. Stockholm)

(Submitted on 27 Mar 2007)

Abstract: There is strong evidence that long duration gamma-ray bursts (GRBs) are produced during the collapse of a massive star. In the standard version of the Collapsar model, a broad-lined and luminous Type Ic core-collapse supernova (SN) accompanies the GRB. This association has been confirmed in observations of several nearby GRBs. Recent observations show that some long duration GRBs are different. No SN emission accompanied the long duration GRBs 060505 and 060614 down to limits fainter than any known Type Ic SN and hundreds of times fainter than the archetypal SN1998bw that accompanied GRB980425. Multi-band observations of the early afterglows, as well as spectroscopy of the host galaxies, exclude the possibility of significant dust obscuration. Furthermore, the bursts originated in star-forming galaxies, and in the case of GRBs060505 the burst was localised to a compact star-forming knot in a spiral arm of its host galaxy. We find that the properties of the host galaxies, the long duration of the bursts and, in the case of GRB060505 the location of the burst within its host, all imply a massive stellar origin. The absence of a SN to such deep limits therefore suggests a new phenomenological type of massive stellar death.

Comments:

Proceedings from the Royal Society meeting on GRBs Sept. 2006

Subjects:

Astrophysics (astro-ph)

Journal reference:

Phil. Trans. R. Soc. A (2007) 365, 1269-1275

DOI:

10.1098/rsta.2006.1994

Cite as:

arXiv:astro-ph/0703678v1