Multi-Wavelength Observations of GRB 050820A: An Exceptionally Energetic Event Followed from Start to Finish

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Accepted to ApJ; 18 pages, 8 figures; High resolution version available at http://www.srl.caltech.edu/~cenko/public/papers/grb

Scientific paper

10.1086/508149

We present observations of the unusually bright and long gamma-ray burst GRB 050820A, one of the best-sampled broadband data sets in the Swift era. The gamma-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 gamma-ray, X-ray, and optical band-passes, something only achieved for a handful of events to date. While the contemporaneous X-rays are the low-energy tail of the prompt emission, the optical does not directly track the gamma-ray flux. Instead, the early-time optical data appear mostly consistent with the forward shock synchrotron peak passing through the optical, and are therefore likely the beginning of the afterglow. On hour time scales after the burst, the X-ray and optical light curves are inconsistent with an adiabatic expansion of the shock into the surrounding region, but rather indicate that there is a period of energy injection. Observations at late times allow us to constrain the collimation angle of the relativistic outflow to theta = 6.8 - 9.3 degrees. Our estimates of both the kinetic energy of the afterglow and the prompt gamma-ray energy release make GRB 050820A one of the most energetic events for which such values could be determined.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Multi-Wavelength Observations of GRB 050820A: An Exceptionally Energetic Event Followed from Start to Finish does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Multi-Wavelength Observations of GRB 050820A: An Exceptionally Energetic Event Followed from Start to Finish, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Multi-Wavelength Observations of GRB 050820A: An Exceptionally Energetic Event Followed from Start to Finish will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-248152

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.