CLAS physics database search results Measurement E159M469 E1-6 V. Burkert 2001 psi(pi+) dsigma/dpsi_pip Data errors deg mcb/rad mcb/rad 30 0.270393 0.048578 90 0.269111 0.0427431 150 0.421828 0.0595874 210 0.375355 0.0616383 270 0.253166 0.042482 330 0.184607 0.0272417