CLAS physics database search results Measurement E159M747 E1-6 V. Burkert 2001 psi(pi-) dsigma/dpsi_pim Data errors deg mcb/rad mcb/rad 30 0.276016 0.0479928 90 0.411237 0.0639162 150 0.35338 0.0549406 210 0.366691 0.0558964 270 0.340221 0.0510043 330 0.262337 0.0433908