A “Shockingly Bright” Gamma-ray Burst

Antonino Cucchiara (University of California Observatories), Dan Perley (California Institute of Technology), and collaborators used GMOS on Gemini North to obtain a spectrum of a gamma-ray burst that had been detected with the Fermi and Swift spacecraft the night of April 26-27. This type of rapid target of opportunity observation is a normal part of Gemini operations, in this case getting the spectrum within 90 minutes of the discovery. The unusual aspect is the result: an extremely bright gamma-ray burst, described in a NASA press release as “shockingly bright.” The brightness has a simple explanation – the host galaxy is relatively nearby, at a redshift of 0.34. Now, the team continues to wait for the GRB afterglow to fade, with more Gemini observations planned to look for a supernova progenitor. The spectrum and a GMOS acquisition image are shown in the Gemini web feature, and reported in: http://gcn.gsfc.nasa.gov/gcn3/14455.gcn3.