CLAS physics database search results Measurement E151M1306 EG4 Xiaochao Zheng 2016 cos(theta_pi+) phi(pi+) A_LL Stat. error Syst. error degrees 0.55 42 0.6233 0.9364 0.0764 0.55 222 -0.2945 0.8573 0.0448 0.55 234 -0.8594 0.7327 0.1015 0.55 246 -0.9422 0.7315 0.1104 0.65 54 0.1098 0.7463 0.0325 0.65 222 -0.5249 0.69 0.0664 0.65 234 0.2868 0.7021 0.0441 0.65 246 -0.0514 0.7189 0.0306 0.65 258 0.1123 0.7376 0.0326 0.75 222 -1.3539 0.7989 0.1556 0.75 234 -0.9798 0.5505 0.1145 0.75 246 -0.4428 0.6098 0.0583 0.75 258 -1.6145 0.6618 0.1845 0.85 222 1.3147 0.7264 0.1513 0.85 234 -0.2664 0.6828 0.0425 0.85 246 -0.3429 0.6094 0.0489