CLAS physics database search results Measurement E151M271 EG4 Xiaochao Zheng 2016 cos(theta_pi+) phi(pi+) A_UL Data errors Systematic errors degrees 0.65 234 0.6072 1.0106 0.0473 0.65 246 1.068 0.9243 0.071 0.65 258 -0.7347 0.4596 0.0535 0.75 246 0.8595 0.9464 0.0598 0.85 246 -0.7341 0.4976 0.0534 0.55 246 -0.7303 0.5488 0.0543 0.65 234 -0.0399 0.518 0.0301 0.65 258 -0.9881 0.5206 0.0681 0.75 234 0.1485 0.5264 0.0314 0.75 246 0.036 0.4636 0.0301