Charged Pion Polarizabilities to two Loops

Abstract

We evaluate the electric and magnetic polarizabilities of charged pions in the framework of chiral perturbation theory at next-to-leading order. This requires a two-loop evaluation of the Compton amplitude near threshold. We estimate the two new low-energy constants which enter the chiral expansion at this order with resonance saturation. The numerical results are compared with presently available experimental information.

Comments: 9 pages, LaTeX, uses epsf.sty and cite.sty, one postscript picture included