CLAS physics database search results Measurement E151M1886 EG4 Xiaochao Zheng 2016 cos(theta_pi+) phi(pi+) A_LL Stat. error Syst. error degrees 0.65 114 0.8841 0.9431 0.0614 0.65 222 -0.219 0.9328 0.0328 0.75 114 -0.9523 0.8313 0.065 0.75 138 0.8194 0.9995 0.058 0.75 210 1.494 0.8713 0.0954 0.75 222 1.4291 0.7831 0.0916 0.75 234 -0.3102 0.9341 0.0354 0.75 246 -0.6064 0.8918 0.0474 0.85 78 -0.4728 0.9926 0.0415 0.85 222 -0.291 0.8393 0.0348 0.85 234 -0.413 0.7803 0.0391 0.85 246 -0.1813 0.8844 0.0319 0.85 258 1.0309 0.8876 0.0693 0.95 246 1.3272 0.6669 0.0858 0.95 258 0.3981 0.7573 0.0385 0.95 270 0.8543 0.7004 0.0598