CLAS physics database search results Measurement E159M756 E1-6 V. Burkert 2001 psi(pi-) dsigma/dpsi_pim Data errors deg mcb/rad mcb/rad 30 0.309507 0.0481802 90 0.394481 0.0577807 150 0.419623 0.0641556 210 0.442426 0.0664323 270 0.367064 0.0527109 330 0.314449 0.0495671