1995/12/20 by J. N. Bahcall, P. I. Krastev
Physics and Astronomy · #Astrophysics #Astrophysics and Cosmic Phenomena #Borexino #Flux (metallurgy) #ICARUS #Limit (mathematics) #Luminosity #Measurements of neutrino speed #Neutrino #Neutrino Physics Research #Neutrino oscillation #Nuclear physics #Oscillation (cell signaling) #Particle physics #Particle physics theoretical and experimental studies #Physics #Range (aeronautics) #Solar neutrino #Solar neutrino problem #Sterile neutrino #hep-ph
paper · pdf · doi:10.1103/physrevd.53.4211
published as Phys.Rev.D53:4211-4225,1996 · 37 pages, uuencoded Z-compressed postscript file (with figures); Submitted to Physical Review D
arxiv created 1995/12/20 · openalex publication_date 1996/04/15 · arxiv updated 2010/11/09 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Individual neutrino fluxes are not well determined by the four operating solar neutrino experiments. Assuming neutrino oscillations occur, the pp electron neutrino flux is uncertain by a factor of 2, the 8B flux by a factor of 5, and the 7Be flux by a factor of 45. For matter-enhanced oscillation (MSW) solutions, the range of allowed differences of squared neutrino masses, \ensuremathΔm2, varies between 4\ifmmode×\else\texttimes\fi10^\mathrm\ensuremath-6 eV2 and 1\ifmmode×\else\texttimes\fi10^\mathrm\ensuremath-4 eV2, while 4\ifmmode×\else\texttimes\fi10^\mathrm\ensuremath-3\ensuremath≤sin22\ensuremathθ\ensuremath≤1.5\ifmmode×\else\texttimes\fi10^\mathrm\ensuremath-2 or 0.5\ensuremath≤sin22\ensuremathθ\ensuremath≤0.9. For vacuum oscillations, \ensuremathΔm2 varies between 5\ifmmode×\else\texttimes\fi10^\mathrm\ensuremath-11 eV2 and 1\ifmmode×\else\texttimes\fi10^\mathrm\ensuremath-10 eV2, while 0.7\ensuremath≤sin22\ensuremathθ\ensuremath≤1.0. The inferred ranges of neutrino parameters depend only weakly on which standard solar model is used. Calculations of the expected results of future solar neutrino experiments (SuperKamiokande, SNO, BOREXINO, ICARUS, HELLAZ, and HERON) are used to illustrate the extent to which these experiments will restrict the range of the allowed neutrino mixing parameters. For example, the double ratio (observed ratio divided by standard model ratio) of neutral current to charged current event rates to be measured in the SNO experiment varies, at 95% confidence limit, over the range 1.0 (no oscillations into active neutrinos), 3.1_\mathrm\ensuremath-1.3+1.8 (small mixing angle MSW), 4.4_\mathrm\ensuremath-1.4+2.0 (large mixing angle MSW), and 5.2_\mathrm\ensuremath-2.9+5.6 (vacuum oscillations). We present an improved formulation of the ``luminosity constraint'' and show that at 95% confidence limit, this constraint establishes the best available limits on the rate of creation of pp neutrinos in the solar interior and provides the best upper limit to the 7Be neutrino flux. The actual rate of creation of solar neutrinos in the solar interior to the rate predicted by the standard solar model can vary (while holding the CNO neutrino flux constant) between 0.55 and 1.08 for pp neutrinos and between 0.0 and 6.35 for 7Be neutrinos. \textcopyright 1996 The American Physical Society.