CLAS physics database search results Measurement E151M1367 EG4 Xiaochao Zheng 2016 cos(theta_pi+) phi(pi+) A_LL Stat. error Syst. error degrees 0.45 42 -0.6557 0.8292 0.0798 0.45 54 -0.49 0.7576 0.0629 0.55 30 -0.2146 0.9331 0.0385 0.55 42 -1.0254 0.816 0.1195 0.55 54 0.0097 0.8884 0.03 0.55 222 -0.4333 0.9331 0.0573 0.55 234 0.9542 0.8036 0.1117 0.55 246 -0.996 0.8859 0.1163 0.65 42 -0.1327 0.8799 0.0335 0.65 54 0.3373 0.781 0.0484 0.65 234 -1.2325 0.8102 0.1422 0.65 246 -0.5012 0.9005 0.064 0.75 234 0.3158 0.7322 0.0466 0.75 246 0.9731 0.7949 0.1138 0.85 234 0.0977 0.6982 0.032