CLAS physics database search results Measurement E216M877 CLAS12 Run Group A Krishna Chandra 2018 psi(pi-) dsigma/dpsi_pim Stat. error Syst. error deg mcbn/rad mcbn/rad mcbn/rad 18 0.0510206 0.00477896 0.00797714 54 0.0469198 0.00747243 0.00909146 90 0.0756061 0.00615011 0.00759292 126 0.112108 0.0110033 0.01174041 162 0.134224 0.00896758 0.01098263 198 0.124028 0.00651824 0.00923314 234 0.0968931 0.00757171 0.00832338 270 0.0692785 0.00550678 0.00706838 306 0.0611782 0.00648115 0.00802887 342 0.0468544 0.0089248 0.00791733