CLAS physics database search results Measurement E151M2368 EG4 Xiaochao Zheng 2016 cos(theta_pi+) phi(pi+) A_LL Stat. error Syst. error degrees 0.85 66 0.9286 0.9009 0.0737 0.85 186 0.9696 1.0431 0.0764 0.85 210 0.4264 0.9707 0.0431 0.85 246 -0.6471 0.8868 0.0557 0.95 234 0.9258 0.9717 0.0735 0.95 246 -0.9966 0.7764 0.0782 0.95 270 -0.8048 0.7538 0.0656 0.95 294 0.7148 0.7894 0.0599