Zenith angle distributions at Super-Kamiokande and SNO and the solution ofthe solar neutrino problem - art. no. 113004

We have performed a detailed study of the zenith angle dependence of the re generation factor and distributions of events at SNO and SK for different s olutions of the solar neutrino problem. In particular, we discuss the oscil latory behavior and the synchronization effect in the distribution for the LMA solution, the parametric peak for the LOW solution, etc. A physical int erpretation of the effects is given. We suggest a new binning of events whi ch emphasizes the distinctive features of the zenith angle distributions fo r the different solutions. We also find the correlations between the integr ated day-night asymmetry and the rates of events in different zenith angle bins. The study of these correlations strengthens the identification power of the analysis.