CLAS physics database search results Measurement E151M1327 EG4 Xiaochao Zheng 2016 cos(theta_pi+) phi(pi+) A_LL Stat. error Syst. error degrees 0.45 42 -0.0279 0.8666 0.0302 0.45 54 -0.0013 0.8965 0.03 0.55 42 -1.1664 0.9153 0.1349 0.55 54 -0.4908 0.8896 0.063 0.55 222 -1.243 0.8409 0.1434 0.55 234 -0.0562 0.7831 0.0307 0.55 246 0.1219 0.846 0.033 0.65 30 0.0253 0.9166 0.0301 0.65 42 -0.991 0.8186 0.1157 0.65 54 0.3511 0.8818 0.0497 0.65 234 -0.1032 0.6108 0.0322 0.65 246 0.4538 0.6367 0.0593 0.75 222 -1.2391 0.7219 0.1429 0.75 234 -1.0632 0.626 0.1236 0.75 246 1.5895 0.6463 0.1818 0.75 258 1.4346 0.7505 0.1646 0.85 222 0.2924 0.7907 0.0446 0.85 234 -1.3186 0.6699 0.1517 0.85 246 -0.5199 0.6243 0.0659