CLAS physics database search results Measurement E216M283 CLAS12 Run Group A Krishna Chandra 2018 psi(pi-) dsigma/dpsi_pim Stat. error Syst. error deg mcbn/rad mcbn/rad mcbn/rad 18 0.434396 0.168305 0.12415254 54 0.266715 0.0177951 0.02590564 90 0.273076 0.0103728 0.02518827 126 0.295072 0.0143731 0.02475356 162 0.309258 0.0110819 0.02395167 198 0.303092 0.0134368 0.02469705 234 0.30884 0.0139258 0.02346062 270 0.30245 0.0127354 0.02551084 306 0.252105 0.0137616 0.02564955 342 0.384224 0.0658061 0.05194196