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We investigate the implications of the SNO charged-current (CC) and electron scattering (ES) measurements of solar 8 B neutrino fluxes for neutrino mass and mixing parameters by performing a global and unified χ 2 analysis of the solar neutrino data in the framework of two neutrino mixing. We consider both ν e − ν active and ν e − ν sterile solutions and perform (i) analysis of the total rates data of Cl, Ga, SK and SNO experiments and (ii) global analysis including the total rates data, the recoil electron spectrum data of SK and the CC spectrum observed at SNO. For the ν e − ν active case the inclusion of the SNO results in the analysis of the total rates reduces(enhances) the goodness-of-fit (GOF) of the SMA(LMA) solution. The flat spectrum observed at SK further favours the LMA solution over the SMA solution and no allowed area is obtained in the SMA region at 3σ level from the global analysis. For the ν e − ν sterile case, with the inclusion of the SNO results, all the solutions are disfavoured with a probability of more than 99% from the total rates analysis while for the global analysis the GOF of these become much worse.

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We examine the solar neutrino problem in the context of the realistic three neutrino mixing scenario including the SNO charged current (CC) rate. The two independent mass squared differences ∆m 2 21 and ∆m 2 31 ≈ ∆m 2 32 are taken to be in the solar and atmospheric ranges respectively. We incorporate the constraints on ∆m , θ 12 and θ 13 from a combined analysis of solar and CHOOZ data. Our aim is to probe the changes in the values of the mass and mixing parameters with the inclusion of the SNO data as well as the changes in the two-generation parameter region obtained from the solar neutrino analysis with the inclusion of the third generation. We find that the inclusion of the SNO CC rate in the combined solar + CHOOZ analysis puts a more restrictive bound on θ 13 . Since the allowed values of θ 13 are constrained to very small values by the CHOOZ experiment there is no qualitative change over the two generation allowed regions in the ∆m 2 21 − tan 2 θ 12 plane. The best-fit comes in the LMA region and no allowed area is obtained in the SMA region at 3σ level from combined solar and CHOOZ analysis.

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