Starling 2007 伽玛暴的宿主星系和尘埃

主要内容:


精彩摘抄:


文章信息:

astro-ph/0701039 [abs, ps, pdf, other] :

Title: Gamma-ray Burst host galaxy gas and dust
Authors: Rhaana Starling (1,2), Ralph Wijers (1), Klaas Wiersema (1) ((1) Amsterdam, (2) Leicester)
Comments: 3 pages, 1 figure, MG11 proceedings

We report on the results of a study to obtain limits on the absorbing columns to wards an initial sample of 10 long Gamma-Ray Bursts observed with BeppoSAX, using a new approach to SED fitting to nIR, optical and X-ray afterglow data, in count space and including the effects of metallicity. When testing MW, LMC and SMC extinction laws we find that SMC-like extinction provides the best fit in most cases. A MW-like ext inction curve is not preferred for any of these sources, largely since the 2175A bump, in principle detectable in all these afterglows, is not present in the data. We rule out an SMC-like gas-to-dust ratio or lower value for 4 of the hosts analysed here (assuming SMC metallicity and extinction law) whilst the remainder of the sample have too large an error to discriminate. We provide an accurate estimate of the line-of-sight extinction, improving upon the uncertainties for the majority of the extinction measurements made in previous studies of this sample.