CLAS physics database search results Measurement E159M857 E1-6 V. Burkert 2001 psi(p) dsigma/dpsi_pr Data errors deg mcb/rad mcb/rad 30 0.294388 0.0579437 90 0.381504 0.0683929 150 0.327101 0.0667134 210 0.348961 0.0663026 270 0.330548 0.0661319 330 0.322001 0.064185