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The unusual X-ray light-curve of GRB 080307: the onset of the afterglow?

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 نشر من قبل Kim Page
 تاريخ النشر 2009
  مجال البحث فيزياء
والبحث باللغة English
 تأليف K.L. Page




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Swift-detected GRB 080307 showed an unusual smooth rise in its X-ray light-curve around 100 seconds after the burst, at the start of which the emission briefly softened. This `hump has a longer duration than is normal for a flare at early times and does not demonstrate a typical flare profile. Using a two component power-law-to-exponential model, the rising emission can be modelled as the onset of the afterglow, something which is very rarely seen in Swift-X-ray light-curves. We cannot, however, rule out that the hump is a particularly slow early-time flare, or that it is caused by upscattered reverse shock electrons.

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