Neutrino Burst Monitoring in Our Galaxy

Baksan underground scintillation telescope (BUST) operates under the program of neutrino burst search since the middle of 1980. We report the current status of the experiment and the results associated with analysis of background events and facility operation stability. We demonstrate the BUST potentialities in detecting neutrino bursts from close supernovae. Over the period from 30.06.1980 to 30.06.2021, the observation time is 35.5 years. During this time, not a single candidate for a neutrino burst has been registered. This leads to an upper bound of the mean frequency of gravitational collapses of stars in our Galaxy of 0.065 year –1 at the 90% confidence level.