CLAS physics database search results Measurement E151M688 EG4 Xiaochao Zheng 2016 cos(theta_pi+) phi(pi+) A_UL Stat. error Syst. error degrees 0.35 78 0.318 0.7502 0.0358 0.45 270 -0.636 0.6157 0.0491 0.45 282 -0.4032 0.5893 0.0388 0.55 222 1.1532 0.7426 0.0766 0.65 126 0.1199 0.7141 0.0309 0.65 138 -0.8561 0.6109 0.0603 0.65 210 -0.3098 0.6722 0.0355 0.65 222 0.822 0.7202 0.0585 0.65 282 1.0872 0.5944 0.073 0.75 66 -0.4482 0.6777 0.0406 0.75 114 -0.7193 0.6491 0.0532 0.75 198 0.9141 0.7969 0.0634 0.75 210 0.1338 0.5709 0.0311 0.75 222 0.6271 0.7372 0.0487 0.75 270 2.1109 2.1109 0.1325 0.75 282 -0.412 0.5392 0.0392 0.75 294 0.6204 0.723 0.0484 0.85 114 0.023 0.5975 0.03 0.85 126 0.4941 0.5834 0.0426 0.85 198 1.0517 0.7494 0.071 0.85 210 0.8615 0.6414 0.0606 0.85 222 -0.1944 0.6733 0.0323 0.85 234 -0.0278 0.563 0.03