CLAS physics database search results Measurement E159M927 E1-6 V. Burkert 2001 psi(pi-) dsigma/dpsi_pim Data errors deg mcb/rad mcb/rad 30 0.107508 0.0226091 90 0.121588 0.0216458 150 0.156953 0.0334367 210 0.12291 0.0220932 270 0.0843863 0.0147737 330 0.0823987 0.0194554