CLAS physics database search results Measurement E151M2436 EG4 Xiaochao Zheng 2016 cos(theta_pi+) phi(pi+) A_LL Stat. error Syst. error degrees 0.75 186 -0.5709 1.0816 0.0511 0.85 102 -0.8341 1.0013 0.0675 0.85 114 -0.9348 0.9996 0.0741 0.85 126 -0.9745 0.9861 0.0768 0.85 210 -0.5849 0.9881 0.052