CLAS physics database search results Measurement E151M2101 EG4 Xiaochao Zheng 2016 cos(theta_pi+) phi(pi+) A_LL Stat. error Syst. error degrees 0.65 114 0.1786 0.979 0.0342 0.75 114 0.8306 1.0078 0.082 0.85 78 0.5809 1.1375 0.0612 0.85 222 -0.2643 1.0324 0.0386 0.85 246 0.1471 0.9209 0.0329 0.95 258 1.7447 2.494 0.1631 0.55 114 -0.2557 0.8919 0.0343 0.65 126 1.529 0.8465 0.1039 0.75 114 0.3167 0.874 0.0364 0.75 126 -0.8391 0.8918 0.0623 0.85 78 0.219 0.9095 0.0332 0.85 222 -0.4094 1.05 0.0401 0.85 234 -0.0747 0.8998 0.0304 0.85 246 -0.0366 0.9866 0.0301 0.85 258 -1.2733 0.9255 0.0881 0.95 210 -2.3546 1.6021 0.1561 0.95 258 1.6788 1.4346 0.1133