CLAS physics database search results Measurement E151M1527 EG4 Xiaochao Zheng 2016 cos(theta_pi+) phi(pi+) A_LL Stat. error Syst. error degrees 0.75 114 0.1422 1.1911 0.0311 0.75 234 -1.1795 1.0274 0.0749 0.85 114 1.9736 0.6807 0.1186 0.85 222 -0.9133 1.0012 0.061 0.85 258 -0.695 0.911 0.0503 0.85 270 -0.0193 0.8447 0.03 0.85 282 -0.4583 0.992 0.0401 0.65 258 1.0719 0.8021 0.0709 0.75 102 -0.0113 0.9463 0.03 0.75 138 1.0307 0.7956 0.0687 0.75 246 0.4188 0.8732 0.0391 0.85 102 -0.5958 0.8798 0.0466 0.85 114 -0.2213 0.8183 0.0328 0.85 138 -0.1281 0.8112 0.031 0.85 270 -0.1721 0.653 0.0317 0.85 294 0.0351 0.7844 0.0301 0.95 270 0.2786 0.6607 0.0343 0.95 282 -0.0945 0.6907 0.0305