CLAS physics database search results Measurement E151M212 EG4 Xiaochao Zheng 2016 cos(theta_pi+) phi(pi+) A_UL Data errors Systematic errors degrees 0.35 282 0.5646 0.817 0.0453 0.45 282 -0.5723 0.4367 0.0457 0.45 294 -0.2329 0.5851 0.0331 0.55 282 -0.8627 0.3542 0.06 0.65 270 2.4997 2.4997 0.1535 0.65 282 -0.4219 0.4938 0.0393 0.65 294 -0.3859 0.5536 0.0379 0.75 270 -0.8696 0.3539 0.0604 0.75 282 -0.3056 0.4905 0.0352 0.95 102 -0.6337 0.4006 0.0485 0.95 138 -1.0251 0.301 0.0686 0.95 162 0.5857 0.746 0.0463 0.35 294 -0.2396 0.4416 0.0335 0.45 282 0.0533 0.456 0.0302 0.55 270 -0.0277 0.4718 0.03 0.55 282 -0.1555 0.3754 0.0315 0.55 294 -0.1913 0.4159 0.0323 0.65 270 -0.1469 0.455 0.0313 0.65 282 0.766 0.429 0.0561 0.75 270 0.1642 0.4377 0.0317 0.75 294 -0.0137 0.4307 0.03 0.85 114 0.4901 0.5037 0.0427 0.95 90 -0.1387 0.4272 0.0312 0.95 102 -0.0678 0.4216 0.0303 0.95 114 0.2248 0.3503 0.0331