  Using moment equations we analyze collective flavor transformation of
supernova neutrinos. We study the convergence of moment equations and find that
numerical results using a few moment converge quite fast. We study effects of
emission angle distribution of neutrinos on neutrino sphere. We study scaling
law of the amplitude of neutrino self-interaction Hamiltonian and find that it
depends on model of emission angle distribution of neutrinos. Dependence of
neutrino oscillation on different models of emission angle distribution is
studied.
