CLAS physics database search results Measurement E151M13 EG4 Xiaochao Zheng 2016 cos(theta_pi+) phi(pi+) A_UL Data errors Systematic errors degrees 0.35 294 -0.7818 0.4074 0.0939 0.45 270 0.0279 0.5063 0.0302 0.45 282 -0.0587 0.3743 0.0307 0.45 294 -0.2078 0.4428 0.0382 0.55 270 -0.1552 0.3614 0.0348 0.55 282 -0.272 0.3313 0.0431 0.65 258 0.3443 0.4419 0.0493 0.65 270 0.252 0.4063 0.0415 0.65 282 -0.1865 0.3399 0.0367 0.75 258 0.1716 0.441 0.0358 0.75 270 -0.5207 0.3424 0.0664 0.75 282 0.2202 0.4433 0.0391 0.85 150 0.4026 0.376 0.0548 0.85 162 -0.0899 0.3533 0.0317 0.85 174 0.6127 0.3761 0.0759 0.85 186 0.239 0.3748 0.0405 0.85 198 -0.0939 0.3754 0.0318 0.85 210 -0.5279 0.3284 0.0671 0.85 222 -0.0132 0.3962 0.03 0.95 138 -0.3732 0.287 0.052 0.95 150 0.1456 0.3217 0.0343 0.95 162 0.3857 0.3575 0.0532 0.95 174 -0.2204 0.3367 0.0391 0.95 186 -0.2677 0.2664 0.0428 0.95 198 -0.5735 0.3056 0.0718 0.95 210 -0.2701 0.3266 0.0429