CLAS physics database search results Measurement E151M11 EG4 Xiaochao Zheng 2016 cos(theta_pi+) phi(pi+) A_UL Data errors Systematic errors degrees 0.45 282 0.6299 0.52 0.0777 0.55 270 0.1909 0.381 0.037 0.55 282 0.3981 0.3443 0.0543 0.65 258 -0.6314 0.3651 0.0778 0.65 270 -0.3195 0.352 0.0471 0.65 282 0.0684 0.4345 0.031 0.75 246 0.5032 0.5131 0.0646 0.75 258 -0.362 0.3518 0.051 0.75 270 -0.0556 0.3312 0.0307 0.75 282 -0.5143 0.4154 0.0658 0.85 150 0.5763 0.4352 0.0721 0.85 162 -0.2071 0.3836 0.0381 0.85 174 -0.1024 0.4277 0.0322 0.85 186 0.043 0.3183 0.0304 0.85 198 0.2711 0.4632 0.043 0.85 210 0.1545 0.3831 0.0348 0.85 222 -0.1004 0.3764 0.0321 0.85 234 -0.566 0.3969 0.071 0.95 150 -0.1182 0.389 0.0329 0.95 162 -0.3315 0.3047 0.0482 0.95 174 0.0488 0.3203 0.0305 0.95 186 0.3489 0.3557 0.0498 0.95 210 -0.0033 0.3503 0.03 0.95 222 -0.329 0.3122 0.048