CLAS physics database search results Measurement E151M2279 EG4 Xiaochao Zheng 2016 cos(theta_pi+) phi(pi+) A_LL Stat. error Syst. error degrees 0.55 90 0.3076 0.7972 0.0374 0.65 78 0.6321 0.9056 0.0548 0.65 90 0.5408 0.7894 0.0494 0.65 114 0.0432 0.947 0.0302 0.75 90 -0.0974 0.8584 0.0308 0.75 114 0.9029 0.7923 0.072 0.75 246 0.984 0.8746 0.0774 0.75 270 0.127 0.8786 0.0314 0.85 54 -0.0283 0.9336 0.0301 0.85 102 0.875 0.8026 0.0702 0.85 222 0.337 0.8442 0.0387 0.85 234 -0.8159 0.8264 0.0663 0.85 246 2.0286 0.7089 0.1501 0.85 270 0.0714 0.7748 0.0304 0.85 282 0.1057 0.8525 0.031 0.85 294 -0.0318 0.73 0.0301 0.85 306 0.7159 0.8056 0.06 0.95 294 -0.1113 0.6436 0.0311 0.95 306 0.4663 0.6987 0.0452