Constraining the environment of GRB 990712 through emission line fluxes.pdfVIP

下载本文档

1
0
约2.54万字
约 5页
2017-04-11 发布于江苏
举报
版权申诉

Constraining the environment of GRB 990712 through emission line fluxes.pdf

1、有哪些信誉好的足球投注网站（book118）网站文档一经付费（服务费），不意味着购买了该文档的版权，仅供个人/单位学习、研究之用，不得用于商业用途，未经授权，严禁复制、发行、汇编、翻译或者网络传播等，侵权必究。。
2、本站所有内容均由合作方或网友上传，本站不对文档的完整性、权威性及其观点立场正确性做任何保证或承诺！文档内容仅供研究参考，付费前请自行鉴别。如您付费，意味着您自己接受本站规则且自行承担风险，本站不退款、不进行额外附加服务；查看《如何避免下载的几个坑》。如果您已付费下载过本站文档，您可以点击这里二次下载。
3、如文档侵犯商业秘密、侵犯著作权、侵犯人身权等，请点击“版权申诉”（推荐），也可以打举报电话：400-050-0827(电话支持时间：9:00-18:30)。
4、该文档为VIP文档，如果想要下载，成为VIP会员后，下载免费。
5、成为VIP后，下载本文档将扣除1次下载权益。下载后，不支持退款、换文档。如有疑问请联系我们。
6、成为VIP后，您将拥有八大权益，权益包括：VIP文档下载权益、阅读免打扰、文档格式转换、高级专利检索、专属身份标志、高级客服、多端互通、版权登记。
7、VIP文档为合作方或网友上传，每下载1次，网站将根据用户上传文档的质量评分、类型等，对文档贡献者给予高额补贴、流量扶持。如果你也想贡献VIP文档。上传文档

Constraining the environment of GRB 990712 through emission line fluxes

a r X i v : a s t r o - p h / 0 6 0 7 1 9 5 v 1 1 0 J u l 2 0 0 6 Astronomy Astrophysics manuscript no. akyletterv5ap February 5, 2008 (DOI: will be inserted by hand later) Constraining the environment of GRB 990712 through emission line fluxes ? Aybu?ke Ku?pcu? Yoldas? 1 , Jochen Greiner 1 , and Rosalba Perna 2 1 Max-Planck-Institut fu?r extraterrestrische Physik, Giessenbachstrasse 1, D-85748 Garching, Germany 2 JILA and Department of Astrophysical and Planetary Sciences, University of Colorado, 440 UCB, Boulder, 80309, USA Received / Accepted Abstract. The energy output in the gamma-ray burst (GRB) prompt emission and afterglow phase is expected to photoionize the surrounding medium out to large radii. Cooling of this gas produces line emission, particularly strong in the optical, whose variability is a strong diagnostics of the gas density and geometry in the close environment of the burst. We present the results of a spectral time series analysis of the host galaxy of GRB 990712 observed up to ～6 years after the burst. We analyze the emission line fluxes together with those of the previous observations of the same GRB, in search for photoionization signatures. We find that the emission line fluxes show no variation within the uncertainities up to 6 years after the burst, and we use the measured line intensities to set a limit on the density of the gas within a few parsecs of the burst location. This is the first time that emission from cooling GRB remnants is probed on years time scales. Key words. Gamma rays: bursts – Stars: circumstellar matter 1. Introduction In the fireball model of GRBs (e.g. Rees Meszaros 1992), the energy released from the collapse of a massive star is con- verted into kinetic energy of thin baryonic shells which ex- pand at ultra-relativistic speeds. After producing the prompt γ-ray emission by internal shocks between different shells, the residual impacts on the surrounding gas and drives an ultra- relativistic shock into the am