No evidence for dust extinction in GRB 050904 at z ~ 6.3

  title={No evidence for dust extinction in GRB 050904 at z ~ 6.3},
  author={Tayyaba Zafar and Darach Watson and Daniele B. Malesani and Paul M. Vreeswijk and Johan P. U. Fynbo and Jens Hjorth and Andrew J. Levan and Michal J. Michalowski Dark and University of Warwick and University of Edinburgh},
  journal={Astronomy and Astrophysics},
Context. Gamma-ray burst (GRB) afterglows are excellent and sensitive probes of gas and dust in star-forming galaxies at all epochs. It has been posited that dust in the early Universe must be different from dust at lower redshifts. To date two reports in the literature directly support this contention, one of which is based on the spectral shape of the afterglow spectrum of GRB050904 at z = 6.295. Aims. Here we reinvestigate the afterglow of GRB050904 to understand cosmic dust at high… Expand

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