C-12(GAMMA,PI(-12(GAMMA,PI(+)P) REACTIONS ACROSS THE DELTA-RESONANCE REGION()N) AND C)

Differential cross-sections from (gamma,pi(+)n) and (gamma,pi(+)p) exp eriments on C-12 are presented together with a microscopic model calcu lation. The comparison of experimental data with theory confirms that quasifree pion production is the dominant process for the (gamma,pi(+) n) reaction. The comparison of (gamma,pi(+)p) with (gamma,pi(+)n) data shows the importance of final state interactions. first time to exper imentally study the strength and the possible mechanisms involved in t he final state interaction. (C) 1997 Published by Elsevier Science B.V .