CLAS physics database search results Measurement E151M620 EG4 Xiaochao Zheng 2016 cos(theta_pi+) phi(pi+) A_UL Stat. error Syst. error degrees 0.45 282 1.4762 0.6888 0.0951 0.65 102 -0.7817 0.6099 0.0564 0.65 222 0.6225 0.7201 0.0485 0.65 234 -0.061 0.6207 0.0302 0.75 102 -0.2533 0.5903 0.0338 0.75 114 -0.3799 0.6575 0.0379 0.75 234 -0.3073 0.5785 0.0354 0.75 246 0.2553 0.6789 0.0338 0.75 258 -0.1199 0.5835 0.0309 0.85 114 -0.7997 0.5903 0.0574 0.85 234 0.5957 0.7038 0.0472 0.85 246 0.6558 0.6211 0.0501 0.85 270 0.7093 0.6157 0.0527 0.95 210 0.1508 0.6308 0.0314 0.95 258 1.1257 0.6521 0.0751 0.95 270 -0.0376 0.5635 0.0301 0.95 282 0.9657 0.5445 0.0662 0.95 294 -0.4138 0.5262 0.0393