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Analysis of solar neutrino problem by means of Nötzold and Nakagawa's approach including the interference term- Hyperbolic-tangent profile for electron density in the sun and exact solution -

Masahiro Kaneyama·Minoru Biyajima
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Abstract

Using an exact solution with the hyperbolic-tangent profile for the electron density in the sun, which is developed by Nötzold and later modified by Nakagawa, we have analyzed the solar neutrino problem. An interference term in their approach is correctly taken into account. Combining the hyperbolic-tangent profile with the BP2000, we obtain a phenomenological fitting in the analytic form. Combining recent observed results for survival probability $P(ν_e \to ν_e)$ by the SNO, SK, SAGE, Gallex, GNO and Homestake Collaborations, we obtain a large mixing angle (LMA) whose figure is looking like a shoulder.

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Masahiro Kaneyama, Minoru Biyajima. 2002-11-18. Analysis of solar neutrino problem by means of Nötzold and Nakagawa's approach including the interference term- Hyperbolic-tangent profile for electron density in the sun and exact solution -. https://arxiv.org/abs/hep-ph/0211273

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