CLAS physics database search results Measurement E151M2189 EG4 Xiaochao Zheng 2016 cos(theta_pi+) phi(pi+) A_LL Stat. error Syst. error degrees 0.45 282 0.77 0.715 0.0634 0.55 294 0.0985 0.7005 0.0308 0.65 66 0.7792 0.7473 0.064 0.65 78 -0.8066 0.7916 0.0657 0.65 270 0.203 0.7341 0.0334 0.65 282 0.6973 0.6658 0.0588 0.65 318 0.357 0.7109 0.0396 0.75 78 0.2484 0.6663 0.035 0.75 258 -0.3889 0.7793 0.0412 0.75 270 -0.0544 0.6971 0.0303 0.75 282 -0.169 0.5819 0.0324 0.75 294 0.4553 0.7386 0.0446 0.85 66 1.183 0.7658 0.0909 0.85 78 0.0729 0.7525 0.0305 0.85 90 -0.1597 0.7319 0.0322 0.85 246 0.7198 0.6808 0.0602 0.85 258 0.9005 0.7205 0.0719 0.85 270 -0.2508 0.7137 0.0351 0.85 282 -0.5592 0.7881 0.0504 0.85 294 0.6829 0.6241 0.0579 0.85 306 0.3214 0.7019 0.038 0.85 318 1.1291 0.715 0.0872 0.95 270 0.4121 0.732 0.0423