Neutrino mass limits from SN1987A

A neutrino signal from the supernova SN1987A is used to place an upper limit on the neutrino mass. If most of the neutrinos must have been emitted within several seconds, as suggested by astrophysical models, the last three of the eleven events observed by the Kamioka detector must correspond to noise or to the tail of a distribution in emission times. If the remaining eight events (which arrived within two seconds of one another) are due to neutrinos emitted within four seconds (a conservative upper limit), bound &≤12 eV/c² is obtained. The Irvine-Michigan-Brookhaven data, with a higher energy threshold, primarily provide information regarding the total duration of the burst.