Fast deuteron production following pion absorption in4He

Abstract
The 4He( pi -,d)nn reaction is studied in a cluster model where the capture of the pion is assumed to take place on a 3He constituent of the target. Good absolute agreement with stopping pion data is achieved for the high energy part of the deuteron spectrum where the n-n system is governed by the 1S0 final state interaction. The relevance of the results for the study of the charge-symmetry-breaking dd to pi 0 4 He reaction is stressed.