Resonant Spin-Flavor Precession Solution to the Solar Neutrino Problem and electron antineutrinos from the Sun

We have found allowed ∆m, μB⊥, sin 2 2θ – regions for the Resonant SpinFlavor Precession Solution (RSFP) [1] to the Solar Neutrino Problem (SNP) fitted with data of all acting solar neutrino experiments. The tipical mass difference region ∆m ∼ 5·10−2·10 eV varying in dependence on the mixing 0 ≤ sin 2θ <∼ 0.05 is allowed for some descrete magnetic field regions in a wide range 30 kG <∼ Bmax <∼ 300 kG for the fixed neutrino transition magnetic moment μ/10μB = μ11 = 1 (free unknown parameter) and for different regular field profiles. Here Bmax is the maximum value of a regular large-scale magnetic field B(r) within the convective zone and the upper value Bmax ≃ 300 kG is chosen from some known MHD constraints [2]. Except of the first allowed range with the lowest field strength 30 kG <∼ Bmax <∼ 70 kG (for the same μ11 = 1) the values Bmax within other descrete allowed regions depend essentially on the profile B⊥(r) of a regular magnetic field in the convective zone of the Sun. For non-zero neutrino mixing (s22 = sin 2 2θ 6= 0) one can find at 99.9% CL (±3σ) an upper limit on the mixing, s22 ≤ s22max ∼ 0.2, originated by the non-observation of electron antineutrinos in the capture reaction ν̄ep → ne in the Superkamiokande (SK) detector (Φν̄ <∼ 0.035ΦνB , Eν >∼ 8.3 MeV [3]). This limit occurs also sensitive to the magnetic field parameter μB⊥. While at 67% CL (±σ) there is another more stringent upper limit s22 ≤ s22max1 ∼ 0.05 coming from inconsistency of gallium experiments with others that is also close to the result s2 <∼ 0.25 [4]. A new allowed region (∆m ≈ 10eV, sin 2θ ≈ 0.01) appears in the case of additional assumption that the Homestake data are 1.3 times less than the experimental event rate. E-mail: [email protected] E-mail: [email protected] E-mail: [email protected] E-mail: [email protected]