Solar Models Based on Helioseismology and the Solar Neutrino Problem

Abstract

We have determined the sound-speed profile in the Sun by carrying out an asymptotic inversion of the helioseismic data from the Low-Degree (l) Oscillation Experiment (LOWL), the Global Oscillation Network Group (GONG), VIRGO on SOHO, the High-l Helioseismometer (HLH), and observations made at the South Pole. We then deduce the density, pressure, temperature, and elemental composition profiles in the solar radiative interior by solving the basic equations governing the stellar structure, with the imposition of the determined sound-speed profile and with a constraint on the depth of the convection zone obtained from helioseismic analysis and the ratio of the metal abundance to the hydrogen abundance at the photosphere. With the exception of the treatment of elements relevant to nuclear reactions, we assume that Z is homogeneous. The chemical composition profiles of hydrogen and helium are then obtained as a part of the solutions. Using the resulting seismic model, we estimate the neutrino fluxes and the neutrino capture rates for the chlorine, gallium, and water Cerenkov experiments. Even if we take into account uncertainties in various input physics, the estimated capture rates are still significantly larger than the observation.