摘要

We analyze the 1496 days of SuperKamiokande data to put limits on the nu(e), (nu) over bar (e), nu(mu) + nu(tau) and (nu) over bar (mu) + (nu) over bar (tau) components of the diffuse flux of supernova neutrinos, in different energy intervals and for different neutrino energy spectra. By considering the presence of only one component at a time, we find the following bounds at 90% CL and for neutrino energy E > 19.3 MeV: Phi(nu e) < 73.3-154 cm(-2) s(-1), Phi((nu) over bare) < 1.4-1.9 cm(-2) s(-1), Phi(nu mu +nu tau) < (1.0-1.4) x 10(3) cm(-2) s(-1) and Phi((nu) over bar mu+($) over bar tau) < (1.3-1.8) x 10(3) cm(-2) s(-1), where the intervals account for varying the neutrino spectrum. In the interval E = 22.9-36.9 MeV, we find Phi(nu e) < 39-54 cm(-2) s(-1), which improves on the existing limit from SNO in the same energy Our results for nu(mu)+nu(tau) and (nu) over bar (mu) + (nu) over bar (tau) improve by about four orders of magnitude the previous best constraints from LSD.

  • 出版日期2008-8