CLAS physics database search results Measurement E216M427 CLAS12 Run Group A Krishna Chandra 2018 psi(pi-) dsigma/dpsi_pim Stat. error Syst. error deg mcbn/rad mcbn/rad mcbn/rad 18 0.302817 0.0261309 0.05959627 54 0.35096 0.0203123 0.04174935 90 0.332557 0.0153353 0.02773667 126 0.346302 0.0109955 0.0256591 162 0.354471 0.011035 0.02658721 198 0.359448 0.0101306 0.02772379 234 0.361007 0.0102444 0.02624267 270 0.352983 0.0198821 0.03291814 306 0.329736 0.0191093 0.03684786 342 0.351589 0.0326758 0.06311349