CLAS physics database search results Measurement E151M761 EG4 Xiaochao Zheng 2016 cos(theta_pi+) phi(pi+) A_UL Stat. error Syst. error degrees 0.75 90 -0.3999 1.6501 0.0476 0.75 102 2.3592 1.6382 0.2198 0.75 270 -1.3357 1.2246 0.1269 0.85 90 4.1173 1.835 0.3812 0.85 114 -0.1577 1.9632 0.0333 0.85 270 2.303 1.7566 0.2147 0.85 294 2.4337 1.7013 0.2266 0.85 306 0.6899 1.606 0.0704 0.65 258 1.7229 1.7229 0.117 0.65 270 -0.2617 0.4818 0.0346 0.75 78 0.0741 0.5201 0.0304 0.75 114 0.0978 0.5795 0.0307 0.75 258 0.2557 0.5188 0.0344 0.75 270 0.7982 0.4767 0.0604 0.75 282 -0.4219 0.405 0.0408 0.75 294 -0.189 0.4457 0.0325 0.85 78 -0.2829 0.4984 0.0353 0.85 102 0.2808 0.5857 0.0352 0.85 246 -0.1069 0.5825 0.0308 0.85 282 0.334 0.5739 0.0372 0.85 306 0.0077 0.5345 0.03 0.95 306 -0.6011 0.754 0.0496