Precise Measurement of Solar Neutrino Oscillation Parameters from Recent Experiments

We analyse the available data of solar neutrino experiments up to the date May 2008, including SK-I, SK-II, SNO phase-I, SNO phase-II and first-generation Ga and Cl experiments. They show great improvement in constraints on solar neutrino oscillation parameters. Together with the new results from long base line reactor experiment KamLAND, the parameters are precisely determined, with 1σ allowed region in Δm²₁₂=7.586^+0.212_-0.203×10^-5 eV², tan²θ₁₂=0.457^+0.076_-0.067.