Momentum Dependence of the Nuclear Isovector Spin Responses from (p→,n→) Reactions at 494 MeV

Complete sets of polarization transfer coefficients have been measured for quasifree ([ital [rvec p]],[ital [rvec n]]) scattering from [sup 2]H, [sup 12]C, and [sup 40]Ca at 494 MeV and scattering angles of 12.5[degree], 18[degree], and 27[degree] ([ital q]=1.2,1.7,2.5 fm[sup [minus]1]). These measurements yield separated transverse ([sigma] [times]/I[ital q]) and longitudinal ([sigma] [center dot]/I[ital q]) isovector spin responses. Comparison of the separated responses to calculations and to electron-scattering responses reveals a strong enhancement in the spin transverse channel. This excess transverse strength masks the effect of pionic correlations in the response ratio.