CLAS physics database search results Measurement E151M749 EG4 Xiaochao Zheng 2016 cos(theta_pi+) phi(pi+) A_UL Stat. error Syst. error degrees 0.65 270 0.2001 0.4883 0.0327 0.75 90 -0.0946 0.4249 0.0306 0.75 270 0.6469 0.4828 0.052 0.75 282 0.478 0.509 0.0434 0.75 294 0.3703 0.4725 0.0386 0.85 66 -0.0066 0.5047 0.03 0.85 90 -0.0153 0.4687 0.03 0.85 282 -0.0898 0.5114 0.0306 0.95 282 0.8817 0.7987 0.0652 0.55 282 -0.8129 1.4703 0.0808 0.65 270 1.6559 1.6724 0.1557 0.65 282 -1.9572 1.3615 0.1831 0.75 270 0.7085 1.5772 0.0719 0.75 282 0.9113 1.7302 0.0893 0.85 66 0.9266 2.2505 0.0906 0.85 90 -2.3308 2.066 0.2172 0.85 102 -3.6034 1.915 0.3339 0.85 294 -0.4132 1.8691 0.0485 0.95 78 5.8368 6.0771 0.5395