Additional time-dependent phase in the flavor-conversion formulas

Instituto de Física Gleb Wataghin, UNICAMP PO Box 6165, 13083-970, Campinas, SP, Brazil

Received: 23 September 2005
Accepted: 15 November 2005

Abstract

In the framework of intermediate wave-packets for treating flavor oscillations, we quantify the modifications which appear when we assume a strictly peaked momentum distribution and consider the second-order corrections in a power series expansion of the energy. By following a sequence of analytic approximations, we point out that an extra time-dependent phase is merely the residue of second-order corrections. Such phase effects are usually ignored in the relativistic wave-packet treatment, but they do not vanish non-relativistically and can introduce some small modifications to the oscillation pattern even in the ultra-relativistic limit.