SOLAR NEUTRINOS - THE MAGNETIC-MOMENT TRANSITION

The resonant spin flip flavour precession of solar neutrinos, a combined effect of matter and magnetic field, is reexamined. The solar magnetic field in the Sun's interior is assumed to be constant [O (105 G)] up to the edge of the convection zone and to decrease linearly, reaching 102 G just below the Sun's surface. The fixed conversion probability lines P(νe → νμ) (for Majorana neutrinos) and P(νeL → νμR) (for Dirac neutrinos are obtained on a magnetic moment, mass square difference parameter space (μ, Δ2m21). Two potential solutions are found agreeing with the experimentally acknowledged neutrino flux deficit. They both require μ = (2-4) × 10-10 μB. One is for Δ2m21 {reversed tilde equals} 3 × 10-4 eV2, corresponding to a resonance near the neutrino production zone in the Sun's core and another for Δ2m21 {reversed tilde equals} (0.7-1) × 10-8 eV2, corresponding to a resonance in the convection zone. Both cases are adiabatic. © 1990.