CLAS physics database search results Measurement E159M441 E1-6 V. Burkert 2001 psi(pi-) dsigma/dpsi_pim Data errors deg mcb/rad mcb/rad 30 0.102131 0.0200844 90 0.136576 0.0213623 150 0.136896 0.0258393 210 0.131753 0.0222674 270 0.129211 0.0199026 330 0.0587401 0.0130875