  Differential cross sections and complete sets of polarization observables are
presented for the Gamow-Teller $^{12}{\rm C}(\vec{p},\vec{n})^{12}{\rm N}({\rm
g.s.},1^+)$ reaction at a bombarding energy of 296 MeV with momentum transfers
$q$ of 0.1 to $2.2{\rm fm}^{-1}$. The polarization transfer observables are
used to deduce the spin-longitudinal cross section, $ID_q$, and spin-transverse
cross sections, $ID_p$ and $ID_n$. The data are compared with calculations
based on the distorted wave impulse approximation (DWIA) using shell-model wave
functions. Significant differences between the experimental and theoretical
results are observed for all three spin-dependent $ID_i$ at momentum transfers
of $q \gtrsim 0.5{\rm fm}^{-1}$, suggesting the existence of nuclear
correlations beyond the shell model. We also performed DWIA calculations
employing random phase approximation (RPA) response functions and found that
the observed discrepancy is partly resolved by the pionic and rho-mesonic
correlation effects.
