CLAS physics database search results Measurement E151M305 EG4 Xiaochao Zheng 2016 cos(theta_pi+) phi(pi+) A_UL Data errors Systematic errors degrees 0.75 114 0.1781 1.039 0.0319 0.75 234 -0.6193 0.7489 0.0479 0.85 114 0.1829 1.0016 0.032 0.85 222 1.4685 1.324 0.0934 0.85 258 0.6703 1.0532 0.0503 0.85 270 -0.9886 0.4822 0.0667 0.85 282 -0.4693 0.7203 0.0412 0.65 258 -0.1131 0.6335 0.0308 0.75 102 0.6809 0.6989 0.0517 0.75 138 -0.1522 0.6301 0.0314 0.75 246 0.1391 0.665 0.0312 0.85 102 0.1233 0.6747 0.031 0.85 114 0.4907 0.6101 0.0427 0.85 138 0.7112 0.6028 0.0533 0.85 270 -0.3872 0.4984 0.0384 0.85 294 0.5265 0.5848 0.0443 0.95 270 -0.0909 0.5082 0.0305 0.95 282 -0.2949 0.5283 0.0351