Statistical analysis of the time structure of the neutrinos from SN 1987A

In the excitement following the observations of neutrino bursts from Supernova 1987A, there has been strong temptation to overinterpret the scant neutrino data: 11 events over 12.4 seconds with energy 7.5--36 MeV from the 2.1 kton Kamiokande II detector plus 8 events over 5.6 second with energy 20--40 MeV from the 5 kton IMB detector. The authors present the results of statistical analysis of the entire data sample (11 + 8 events over 12.4 seconds) for consistency and for dynamical evidence for cooling of the nascent neutron star. They attempt to fit the data with three simple cooling models, power law cooling, T = Ts(at/n + 1)-n, for various values of n, exponential cooling, T = Tse- at (the limit of power law cooling as n → ∞) and loaded sphere cooling