CLAS physics database search results Measurement E216M337 CLAS12 Run Group A Krishna Chandra 2018 psi(pi-) dsigma/dpsi_pim Stat. error Syst. error deg mcbn/rad mcbn/rad mcbn/rad 18 0.414937 0.0242428 0.05280447 54 0.430625 0.0235288 0.06046191 90 0.499314 0.0226735 0.04173982 126 0.53002 0.014502 0.04061919 162 0.629786 0.0138549 0.0477064 198 0.614514 0.0272547 0.04981257 234 0.546247 0.0138752 0.04336918 270 0.478481 0.0148969 0.03999668 306 0.499374 0.0550415 0.05679472 342 0.5118 0.0821831 0.07797682