Stephen G. Gasiorowicz

Equations for neutrino propagation in matter

We study the dynamical equations for two-family neutrino oscillations in a medium of continuously-varying density. We can find explicit solutions to these equations in terms of series of nested integrals. These solutions can serve as a basis for numerical calculation of these processes or for further study of their analytical properties.

An approximation method for bound states in quantum chromodynamics

A method for extracting hadron states in confining field theories (QCD) from the asymptotic behavior of two-point functions and the imposition of confinement through the removal of cuts is reviewed and generalized to take explicit account of the spin-12 nature of the constituents. The role of perturbative corrections is discussed and explored numerically with anomalous dimension for arbitrary spin J and to sixth order for the specific example of spin-1 hadronic states. We conclude that the effects of these are significant though incapable of leading to linear Regge trajectories, and that the main features of the hadron spectrum must come from the non-perturbative inverse power corrections.