Study of Delta-Delta excitations in the reaction n+p -> d+pi+pi
  The deuteron spectrum in n+p -> d+pi+pi at k_n = 1.88 GeV/c and theta_d = 0 deg is explained by considering a Delta-Delta excitation as the reaction mechanism for the 2pi production. We study the influence of intermediate Delta-Delta and Delta-Nucleon interactions on the spectrum. The angular distribution of the pions is predicted. 
C. A. Mosbacher and F. Osterfeld