CLAS physics database search results Measurement E151M1131 EG4 Xiaochao Zheng 2016 cos(theta_pi+) phi(pi+) A_UL Stat. error Syst. error degrees 0.75 234 0.7278 0.871 0.0611 0.85 66 -0.5503 0.5912 0.0502 0.85 78 -0.2348 0.5781 0.0346 0.85 210 0.9871 0.8602 0.0781 0.85 234 0.9097 0.716 0.0729 0.85 246 1.3062 0.6616 0.1001 0.85 258 -0.133 0.6038 0.0315 0.85 270 0.9145 0.7404 0.0733 0.95 246 -0.3184 0.5919 0.038 0.95 258 0.0803 0.6522 0.0306 0.95 270 0.823 0.6022 0.0672 0.95 282 0.5174 0.7191 0.0483 0.95 294 -0.3212 0.5232 0.0381 0.95 306 1.179 0.685 0.0912