CLAS physics database search results Measurement E159M37 E1-6 V. Burkert 2001 psi(pi+) dsigma/dpsi_pip Data errors deg mcb/rad mcb/rad 30 0.467503 0.0763024 90 0.56043 0.0856267 150 0.751634 0.115666 210 0.716178 0.102748 270 0.447997 0.0701414 330 0.451137 0.0681124