CLAS physics database search results Measurement E159M55 E1-6 V. Burkert 2001 psi(pi+) dsigma/dpsi_pip Data errors deg mcb/rad mcb/rad 30 0.491518 0.0794442 90 0.542286 0.0832761 150 0.915052 0.134571 210 0.946855 0.140215 270 0.521327 0.0790194 330 0.485417 0.0759175