CLAS physics database search results Measurement E151M432 EG4 Xiaochao Zheng 2016 cos(theta_pi+) phi(pi+) A_UL Data errors Systematic errors degrees 0.55 222 0.3219 0.6177 0.0372 0.55 234 0.1034 0.6408 0.0532 0.65 234 0.8185 0.7523 0.0589 0.65 246 1.0005 0.7225 0.0688 0.75 138 -0.0641 0.6659 0.0303 0.75 162 -1.0519 0.6685 0.0717 0.75 222 0.7995 0.7141 0.0579 0.75 246 0.6288 0.5917 0.0492 0.85 222 -0.1565 0.7218 0.0315 0.85 234 -1.1108 0.5976 0.075 0.85 246 -0.6002 0.5717 0.0478 0.85 258 0.9684 0.7012 0.067 0.95 138 -0.2494 0.6357 0.0337 0.55 246 -0.079 1.0366 0.0304 0.65 222 -0.9228 0.6769 0.0631 0.65 234 1.2219 1.1909 0.0795 0.75 234 -0.0249 1.0337 0.03 0.75 246 0.5255 1.0194 0.0436 0.75 258 1.9516 1.3449 0.1213 0.85 234 0.3361 0.871 0.0362 0.85 246 0.6906 0.8543 0.0513