CLAS physics database search results Measurement E151M1898 EG4 Xiaochao Zheng 2016 cos(theta_pi+) phi(pi+) A_LL Stat. error Syst. error degrees 0.45 270 -0.59 0.8945 0.0467 0.45 282 -1.198 0.8459 0.0785 0.55 126 -0.1286 0.9766 0.031 0.55 210 -0.6196 0.9341 0.0481 0.55 270 1.7693 0.7849 0.1113 0.65 114 0.0996 0.9084 0.0306 0.65 126 -0.3404 0.9105 0.0364 0.65 138 -0.7451 0.9552 0.0542 0.65 210 0.9485 0.8948 0.0648 0.75 210 -1.6671 0.6859 0.1054 0.75 222 -0.7032 0.8454 0.0521 0.75 234 -1.1824 0.88 0.0777 0.75 246 0.3617 0.9192 0.0372 0.75 282 -0.1588 0.8113 0.0315 0.75 294 0.0305 0.7442 0.0301 0.85 102 2.2876 0.6301 0.1418 0.85 114 0.4806 0.8963 0.0418 0.85 210 1.0733 0.8198 0.0716 0.85 222 -1.1239 0.7194 0.0744 0.85 234 0.3448 0.7169 0.0366 0.85 246 -0.1584 0.8588 0.0315 0.95 234 0.8489 0.6535 0.0596