Dirac neutrino magnetic moment and neutrino emission from supernova

by Dr Oleg Lychkovskiy (ITEP, Moscow)

Wednesday 18 Mar 2009, 11:00 → 12:00 Europe/Zurich

1/1-025 (CERN)

Immediately after the SN1987A observation it was realized that a high-energy part of the supernova neutrino signal (Eν ~ (100-200) MeV) may appear (in addition to the normal neutrino signal with Eν~ (10-40) MeV) due to the Dirac magnetic moment of neutrino [1]. In that early papers the number of high-energy neutrinos in detectors was estimated as a function of the magnetic moment. However, the estimates had a two-order uncertainty, basically due to a very rude supernova model used. Some time ago it was argued that the result may be substantially improved and that such improvement is very desirable in view of increasing sensitivities of the neutrino detectors [2]. An accurate expression for the number of high-energy neutrinos in detectors will be necessary to extract information about the neutrino Dirac magnetic moment from the future supernova neutrino signal. In this contribution an improved calculation of the supernova core luminosity in right neutrinos is presented. The main improvement is due to the usage of a dynamical model of supernova. Also an accurate expression for the neutrino spin flip rate [3] is used. Sensitivities of Super-Kamiokande and future 0.5-Mt neutrino detectors to the Dirac neutrino magnetic moment signatures in the supernova neutrino signal are estimated. [1] I.Goldman, Y.Aharonov, G.Alexander and S.Nussinov, Phys.Rev.Lett.60, 1789 (1987); J.M.Lattimer and J.Cooperstein, Phys.Rev.Lett. 61, 23 (1988); R.Barbieri and R.N.Mohapatra, Phys.Rev.Lett.61, 27 (1988); D.Notzold, Phys.Rev.D 38, 1658 (1988) [2] O. Lychkovskiy, a talk given at the 51th MIPT Scientific Conference, arXiv:0804.1005 [3] A.V.Kuznetsov and N.V.Mikheev, JCAP 0711:031, 2007