Spectral components in the bright, long GRB 061007: properties of the photosphere and the nature of the outflow
2011 (English)In: Monthly notices of the Royal Astronomical Society, ISSN 0035-8711, E-ISSN 1365-2966, Vol. 414, no 3, 2642-2649 p.Article in journal (Refereed) Published
We present a time-resolved spectral analysis of the bright, long GRB 061007 (z = 1.261) using Swift and Suzaku data. We find that the prompt emission of the burst can be equally well explained by a photospheric component together with a power law as by a Band function, and we explore the implications of the former model. The photospheric component, which we model with a multicolour blackbody, dominates the spectra and has a very stable shape throughout the burst. This component provides a natural explanation for the hardness-intensity correlation seen within the burst and also allows us to estimate the bulk Lorentz factor and the radius of the photosphere. The power-law component dominates the fit at high energies and has a nearly constant slope of -1.5. We discuss the possibility that this component is of the same origin as the high-energy power laws recently observed in some Fermi bursts.
Place, publisher, year, edition, pages
2011. Vol. 414, no 3, 2642-2649 p.
radiation mechanisms: general, gamma-ray burst: individual: GRB 061007
Astronomy, Astrophysics and Cosmology
IdentifiersURN: urn:nbn:se:su:diva-67002DOI: 10.1111/j.1365-2966.2011.18582.xISI: 000292977600065OAI: oai:DiVA.org:su-67002DiVA: diva2:470026
authorCount :72011-12-282011-12-222011-12-28Bibliographically approved