ULTRAHIGH-ENERGY NEUTRINOS FROM GAMMA-RAY BURSTS

Protons accelerated to high energies in the relativistic shocks that g enerate gamma ray bursts photoproduce pions, and then neutrinos in sit u. I show that ultrahigh energy neutrinos (>10(19)eV) are produced dur ing the burst and the afterglow. A larger flux, also from bursts, is g enerated via photoproduction off cosmic microwave background photons i n flight but is not correlated with currently observable bursts, appea ring as a bright background. Adiabatic and synchrotron losses from pro tons, pions, and muons are negligible. Temporal and directional coinci dences with bursts detected by satellites can separate correlated neut rinos from the background.