KamLAND data and the solution to the solar neutrino problem

• Autor(a) principal: Holanda,P. C. de
• Data de Publicação: 2004
• Outros Autores: Smirnov,A. Yu.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Brazilian Journal of Physics
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-97332004000700019

The first KamLAND results are in a very good agreement with the predictions made on the basis of the solar neutrino data and the LMA realization of the MSW mechanism. We perform a combined analysis of the KamLAND (rate, spectrum) and the solar neutrino data with a free boron neutrino flux fB. The best fit values of neutrino parameters are deltam² = 7.1.10-5 eV², tan² theta = 0.40 and fB = 1.04 with the 1sigma intervals: deltam² = (6.4 - 8.4). 10-5 eV², tan² theta = 0.33 - 0.48. We find the 3sigma upper bounds: deltam² < 1.7 . 10-4 eV² and tan² theta< 0.64, and the lower bound deltam² > 4.8 . 10-5 eV². In the best fit point we predict for SNO: CC/NC = <IMG SRC="/img/revistas/bjp/v34n4a/a19img01.gif">and <IMG SRC="/img/revistas/bjp/v34n4a/a19img02.gif" > or = 3.0 ± 0.8% (68% C.L.), and <IMG SRC="/img/revistas/bjp/v34n4a/a19img02.gif">< 6% at the 3sigma level. Further improvements in the determination of the oscillation parameters are discussed and implications of the solar neutrino and KamLAND results are considered.