CLAS physics database search results Measurement E151M786 EG4 Xiaochao Zheng 2016 cos(theta_pi+) phi(pi+) A_UL Stat. error Syst. error degrees 0.75 90 1.7472 1.3628 0.164 0.75 246 1.0069 1.2292 0.0976 0.85 90 -0.7109 1.4185 0.0721 0.85 102 3.5364 1.5358 0.3278 0.95 306 3.981 3.4559 0.3686 0.65 270 0.2937 0.6272 0.0357 0.75 78 -0.3618 0.5673 0.0383 0.75 102 -0.42 0.5891 0.0407 0.85 90 -0.7868 0.5505 0.0597 0.85 102 0.1478 0.6212 0.0315 0.85 114 -0.936 0.5243 0.0684 0.85 246 0.4258 0.687 0.041 0.85 270 -0.2413 0.6152 0.0339 0.85 282 -0.8715 0.5281 0.0646 0.85 294 -0.323 0.5295 0.0367 0.95 270 -1.2469 0.8252 0.0871 0.95 294 1.099 0.938 0.0781