CLAS physics database search results Measurement E151M2421 EG4 Xiaochao Zheng 2016 cos(theta_pi+) phi(pi+) A_LL Stat. error Syst. error degrees 0.75 210 -0.3244 1.1306 0.0381 0.85 102 1.133 0.9944 0.0875 0.85 114 0.4096 0.9971 0.0422 0.85 126 1.7004 1.0622 0.1269 0.85 174 -1.1043 1.0681 0.0855 0.85 198 -0.0165 0.9764 0.03 0.85 210 0.0094 0.978 0.03 0.85 222 0.4144 1.006 0.0425