Origin of anomalous values ofσ(π+,π+′p)/σ(π−,π−′p)

Abstract

Results of recoil-corrected continuum shell model calculations are presented for {sup 4}He({pi},{pi}{sup {prime}}p){sup 3}H. The extremely large values of {sigma}({pi}{sup +},{pi}{sup +{prime}}p)/{sigma}({pi}{sup {minus}},{pi}{sup {minus}{prime}}p) are shown to be a result of neutron excitations which couple to outgoing proton channels. The large ratio will occur in regions where neutron excitations increase rapidly in a particular channel and, therefore, may be a signal for giant resonances. {copyright} {ital 1997} {ital The American Physical Society}