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P.W.A. Roming, P. Schady, D.B. Fox (PSU), B. Zhang, E. Liang (UNLV)
Observations on timescales of minutes to less than an hour of gamma-ray burst (GRBs) afterglows by the Swift Ultra-Violet/Optical Telescope (UVOT) reveals that the optical component in many cases is suppressed. This is in marked contrast to the bright optical flashes believed to be the norm in the pre-Swift era. Some potential causes for suppression of afterglows include: high redshift or the distance effect, very high redshift or IGM absorption, extinction by dust, low-density environment and a high cooling frequency, and empirical relation such as low spectral index. Here we present highly magnetized outflows as an alternative.
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Bulletin of the American Astronomical Society, 37 #4
© 2005. The American Astronomical Soceity.