Multiwavelength Observations of GRB 050820A: An Exceptionally Energetic Event Followed from Start to Finish

  title={Multiwavelength Observations of GRB 050820A: An Exceptionally Energetic Event Followed from Start to Finish},
  author={S. Bradley Cenko and Mansi M. Kasliwal and Fiona A. Harrison and Valentin D. Pal'shin and Dale A. Frail and P. Brian Cameron and Edo Berger and Derek B. Fox and Avishay Gal-yam and Shrinivas R. Kulkarni and Dae-Sik moon and Ehud Nakar and Eran. O. Ofek and Bryan Edward Penprase and Paul A. Price and Re’em Sari and Brian P. Schmidt and Alicia Margarita Soderberg and R. L. Aptekar' and Dmitry D. Frederiks and Sergey Golenetskii and David N. Burrows and Roger A. Chevalier and N. C. Gehrels and Patrick McCarthy and J A Nousek and Tsvi Piran},
  journal={The Astrophysical Journal},
  pages={490 - 506}
We present observations of the unusually bright and long γ-ray burst GRB 050820A, one of the best sampled broadband data sets in the Swift era. The γ-ray light curve is marked by a soft precursor pulse some 200 s before the main event; the lack of any intervening emission suggests that it is due to a physical mechanism distinct from the GRB itself. The large time lag between the precursor and the main emission enabled simultaneous observations in the γ-ray, X-ray, and optical bandpasses… 

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