CLAS physics database search results Measurement E151M2221 EG4 Xiaochao Zheng 2016 cos(theta_pi+) phi(pi+) A_LL Stat. error Syst. error degrees 0.65 78 -0.1784 0.8333 0.0327 0.65 90 0.6809 0.8292 0.0578 0.65 102 -0.7461 0.8647 0.0619 0.65 258 -1.335 0.6923 0.1013 0.65 282 1.1546 0.7925 0.0889 0.75 78 -0.6276 0.7614 0.0545 0.75 90 1.2188 0.7299 0.0933 0.75 102 -0.0699 0.8755 0.0304 0.75 246 0.2428 0.8615 0.0348 0.75 258 0.2254 0.7181 0.0342 0.75 270 1.0698 0.7152 0.0832 0.75 282 0.309 0.8238 0.0374 0.75 294 0.2201 0.8181 0.034 0.85 78 -1.6735 0.7214 0.125 0.85 102 1.5575 0.7831 0.1169 0.85 246 1.6964 0.6223 0.1266 0.85 258 -0.2807 0.5972 0.0363 0.85 270 0.3941 0.7106 0.0414 0.85 282 1.0938 0.7539 0.0848 0.85 294 0.9714 0.8277 0.0766 0.85 306 0.6809 0.7951 0.0578 0.85 318 0.732 0.772 0.061 0.95 246 -0.4743 0.8043 0.0456 0.95 270 0.7043 0.688 0.0592 0.95 282 -0.062 0.7379 0.0303 0.95 294 0.9453 0.7043 0.0748