CLAS physics database search results Measurement E151M912 EG4 Xiaochao Zheng 2016 cos(theta_pi+) phi(pi+) A_UL Stat. error Syst. error degrees 0.55 126 -0.3852 0.9402 0.0465 0.65 222 0.8644 1.0686 0.0852 0.85 102 -0.8741 0.9688 0.0861 0.85 126 -0.6798 1.2213 0.0695 0.45 270 -0.2097 0.636 0.033 0.55 270 1.0625 0.6903 0.0759 0.65 114 -0.4352 0.6258 0.0414 0.65 138 0.0435 0.7419 0.0301 0.65 222 0.5582 0.7596 0.0473 0.75 126 -0.6847 0.6823 0.054 0.75 210 1.3793 0.8038 0.0954 0.75 282 -1.0999 0.4615 0.0782 0.85 114 -1.4763 0.5601 0.1014 0.85 210 0.7125 0.8984 0.0556 0.85 222 1.5632 0.8142 0.1069