Effective Isovector NN Interaction Strengths Determined from the S 28 i ( p → , p → ′ ) S 28 i ( 6 − , T = 1 ) Reaction

We report measurements of {sigma}({theta}), A({theta}), and polarization transfer for the {sup 28}Si({rvec p},{rvec p}{sup {prime}}){sup 28}Si reaction to the 6{sup {minus}},T=1 state at 14.36MeV initiated with 198MeV polarized protons. Normalization of the transition strength in the distorted-wave impulse approximation (DWIA) to inelastic electron scattering overpredicts the spin-longitudinal cross section by more than a factor of 2, while the spin-transverse cross section is nearly correct and the spin-orbit cross section is underpredicted. A reduced in-medium {rho}-meson mass reproduces some of these features, while strong relativistic mean field or Pauli blocking effects are too small. {copyright} {ital 1997} {ital The American Physical Society}