CLAS physics database search results Measurement E159M281 E1-6 V. Burkert 2001 psi(p) dsigma/dpsi_pr Data errors deg mcb/rad mcb/rad 30 0.59572 0.0919663 90 0.448781 0.0659342 150 0.45431 0.0717603 210 0.503737 0.0775411 270 0.435223 0.0666298 330 0.569729 0.0914327