CLAS physics database search results Measurement E151M2394 EG4 Xiaochao Zheng 2016 cos(theta_pi+) phi(pi+) A_LL Stat. error Syst. error degrees 0.65 126 0.7361 1.0028 0.0612 0.65 138 -1.3045 1.3529 0.0992 0.75 102 0.2226 1.1074 0.0341 0.75 114 -1.0957 1.1552 0.0849 0.75 210 -2.2964 0.8595 0.1692 0.75 222 -1.7867 0.8906 0.133 0.85 102 -1.8512 0.7171 0.1375 0.85 114 -1.2964 0.8114 0.0987 0.85 126 -1.8238 0.9649 0.1356 0.85 174 1.9268 0.9821 0.1429 0.85 186 1.2198 0.797 0.0934 0.85 198 -0.8111 0.8497 0.066 0.85 210 -0.7871 0.9968 0.0645