CLAS physics database search results Measurement E151M1084 EG4 Xiaochao Zheng 2016 cos(theta_pi+) phi(pi+) A_UL Stat. error Syst. error degrees 0.55 114 -0.0578 0.9646 0.0303 0.65 114 -0.2204 0.7303 0.0341 0.65 126 0.3758 0.9257 0.0407 0.75 114 -1.1423 0.7294 0.0887 0.75 126 -1.3981 0.6602 0.1065 0.75 138 -1.2193 0.7128 0.094 0.75 210 -0.5678 0.7989 0.0512 0.75 222 0.666 0.9207 0.0572 0.75 234 0.4748 0.945 0.0459 0.85 90 -1.2001 0.567 0.0927 0.85 102 -0.7026 0.6642 0.0595 0.85 114 -0.6489 0.778 0.0561 0.85 210 0.9779 0.9775 0.0775 0.85 222 -0.2047 0.763 0.0335 0.85 234 -0.759 0.6578 0.0631 0.85 246 2.3133 0.8884 0.1717 0.95 246 3.4616 3.4616 0.2548