CLAS physics database search results Measurement E151M1405 EG4 Xiaochao Zheng 2016 cos(theta_pi+) phi(pi+) A_LL Stat. error Syst. error degrees 0.35 42 0.7776 0.7558 0.0927 0.35 54 -0.0799 0.6942 0.0313 0.35 66 1.0722 0.8927 0.1246 0.45 42 -0.141 0.6655 0.034 0.45 54 0.413 0.6666 0.0554 0.45 66 1.1919 0.7507 0.1377 0.45 234 0.8723 0.7141 0.1029 0.55 54 0.6642 0.7972 0.0807 0.55 222 0.8464 0.7371 0.1001 0.55 234 -0.194 0.6928 0.0371 0.55 246 -1.2468 0.6638 0.1438 0.65 210 -1.138 0.7465 0.1318 0.65 222 -0.5246 0.7995 0.0663 0.65 234 -0.1271 0.6579 0.0332 0.65 246 0.4252 0.7214 0.0566 0.75 222 -0.7266 0.7242 0.0873 0.75 234 0.1258 0.6583 0.0332 0.75 246 1.7331 0.5904 0.1978 0.85 222 -0.6645 0.6492 0.0807 0.85 234 0.5556 0.6757 0.0695