CLAS physics database search results Measurement E159M9 E1-6 V. Burkert 2001 psi(pi-) dsigma/dpsi_pim Data errors deg mcb/rad mcb/rad 30 0.114027 0.0236207 90 0.272484 0.0437375 150 0.322573 0.0485583 210 0.277313 0.0438986 270 0.394508 0.05915 330 0.159036 0.0317771