CLAS physics database search results Measurement E151M1107 EG4 Xiaochao Zheng 2016 cos(theta_pi+) phi(pi+) A_UL Stat. error Syst. error degrees 0.75 102 -0.451 0.7821 0.0446 0.75 234 -0.6098 0.7811 0.0537 0.85 54 -0.7152 0.7295 0.0603 0.85 222 1.6206 0.836 0.1222 0.85 234 -0.8274 0.7274 0.0675 0.85 246 0.6996 0.8526 0.0593 0.85 258 -0.2127 0.7195 0.0338 0.85 270 -0.4246 0.7511 0.0432 0.85 282 1.5587 0.8597 0.1178 0.95 270 -0.482 0.6991 0.0463 0.95 282 -0.4041 0.6586 0.0421 0.95 294 -0.7038 0.6326 0.0596 0.95 306 0.8542 0.8662 0.0693 0.95 318 0.2643 0.718 0.0357