Evidence for pionic enhancement in quasifree Δ production in the 12C(p[downward right arrow],n[downward right arrow]) reaction

We present (p↘,n↘) spin observable measurements in the quasielastic and quasifree delta region of excitation taken on the targets 2H and 12C at 0° and 795 MeV proton energy. These observables have been used to form the spin–longitudinal (σ⋅q) and spin–transverse (σ×q) cross sections. Good agreement is found between experiment and theory in the spin–longitudinal channel.