CLAS physics database search results Measurement E159M847 E1-6 V. Burkert 2001 psi(pi+) dsigma/dpsi_pip Data errors deg mcb/rad mcb/rad 30 0.29691 0.0499318 90 0.296617 0.0492667 150 0.333277 0.0535349 210 0.412809 0.0699812 270 0.284225 0.0472998 330 0.306591 0.0519038