MO-P7-3 15:15

Extraction Of The Solar Neutrino Mixing Parametars With Sudbury Neutrino Observatory (SNO), And The Effect Of Active-sterile Neutrino Mixing*, Gordana Tesic , Alain Bellerive , Carleton University — The Sudbury Neutrino Observatory (SNO) studies the fundamental properties of elementary particles called neutrinos, which are produced via nuclear fusion reactions in the core of the Sun. Recently published results from SNO provide direct evidence for flavor conversion of solar neutrinos and measurement of the total neutrino flux which is in agreement with the Standard Solar Model (SSM) prediction. The best fit for the neutrino oscillation parameters, the mass squared difference (Dm²₁₂) and the mixing angle (q₁₂), using SNO data and the Maximum Likelihood Technique with floating systematic uncertainties, in the model with two active neutrinos, will be presented. Additionally, studies of the effects due to sterile and a third active neutrino in the theoretical predictions for various solar neutrino experiments have been performed. The solar neutrino survival probabilities, obtained by numerically solving the neutrino propagation equations inside the Sun, vacuum and the Earth, in a system with two active and one sterile neutrinos, can be used to set a limit for the fraction of a sterile neutrino component in the solar neutrino flux. The analysis of three active neutrino generations shows the modification of the solar neutrino energy profile due to the mixing with the third mass eigenstate. The ultimate goal of this analysis is to place a limit on the third mixing angle (q₁₃) by combining the measurements from SNO, other solar neutrino experiments and the KamLAND antineutrino experiment. The study of the sterile neutrino component is essential for a better understanding of the neutrinos properties, as well as the structure and evolution of our Universe.

* This work is being supported by Carleton University and the SNO collab.

* This work is being supported by Carleton Univ., SNO collab.