CLAS physics database search results Measurement E216M139 CLAS12 Run Group A Krishna Chandra 2018 psi(pi-) dsigma/dpsi_pim Stat. error Syst. error deg mcbn/rad mcbn/rad mcbn/rad 18 0.538269 0.192368 0.15158925 54 0.444528 0.0777328 0.08656294 90 0.324172 0.0160215 0.03004811 126 0.381387 0.0141883 0.02884945 162 0.41632 0.0155751 0.03754281 198 0.406574 0.0138792 0.03181231 234 0.388397 0.0178451 0.03722814 270 0.393919 0.0436362 0.04694609 306 0.324262 0.0218332 0.03939256 342 0.415498 0.060432 0.0923065