The separated isovector spin-longitudinal and spin-transverse responses from a recent ( $\overrightarrow{p},\overrightarrow{n}$) quasifree experiment at 494 MeV are analyzed in a Glauber theory framework up to two-step contributions. Nuclear correlations are treated in the continuum random phase approximation, accounting for the spreading width of the particle-hole states. A good description of the spin-longitudinal response is achieved, hinting at some evidence of pionic effects in the quasielastic region. The spin-transverse response is underestimated, and we show that multistep contributions, while sizable, are not sufficient to provide an explanation of the discrepancy.

• Received 13 February 1995

DOI:https://doi.org/10.1103/PhysRevLett.75.29