CLAS physics database search results Measurement E159M73 E1-6 V. Burkert 2001 psi(pi+) dsigma/dpsi_pip Data errors deg mcb/rad mcb/rad 30 0.462569 0.0739253 90 0.588334 0.0904214 150 0.90219 0.132318 210 0.995476 0.145384 270 0.524397 0.0824102 330 0.459849 0.0717416