CLAS physics database search results Measurement E151M1766 EG4 Xiaochao Zheng 2016 cos(theta_pi+) phi(pi+) A_LL Stat. error Syst. error degrees 0.65 102 1.4511 0.6788 0.0929 0.65 270 -0.0837 0.7101 0.0304 0.75 78 -1.4346 0.695 0.092 0.75 90 1.5665 0.597 0.0996 0.75 102 0.4283 0.7105 0.0397 0.75 294 -0.8991 0.6946 0.0622 0.85 90 -0.0256 0.7878 0.03 0.85 102 2.2219 2.2219 0.1379 0.85 222 -0.2803 0.7468 0.0345 0.85 234 1.0763 0.6729 0.0718 0.85 270 -0.2139 0.7028 0.0327 0.85 282 -0.1554 0.7033 0.0314 0.85 294 0.8644 0.6566 0.0604 0.95 234 -0.2042 0.7148 0.0325 0.95 294 0.4764 0.6282 0.0416