ADVANCES IN HIGH ENERGY PHYSICS, 2012 (SCI-Expanded)
We examine the effect of excited neutrinos on the annihilation of relic neutrinos with ultrahigh energy cosmic neutrinos for the nu(nu) over bar -> gamma gamma process. The contributions of the excited neutrinos to the neutrino-photon decoupling temperature are calculated. We see that photon-neutrino decoupling temperature can be significantly reduced below the obtained value of the Standard Model with the impact of excited neutrinos.