Interestingly, an April 18 paper in the journal Nature reported that upper limits for neutrinos measured from IceCube are low enough that gamma-ray bursts are unlikely to be the sole source of ultra-high energy cosmic rays.

CNN: Why gamma-ray burst shocked scientists

The world's most powerful neutrino telescope, IceCube, uses Antarctic ice as the detector volume, with electronic equipment sunk throughout a cubic kilometer of ice -- enough water to fill a million swimming pools -- to detect signals from neutrinos interacting with the ice.

CNN: Why gamma-ray burst shocked scientists