CLAS physics database search results Measurement E159M523 E1-6 V. Burkert 2001 psi(pi+) dsigma/dpsi_pip Data errors deg mcb/rad mcb/rad 30 0.387776 0.0601876 90 0.377242 0.0566807 150 0.535136 0.0839711 210 0.500201 0.0766341 270 0.373833 0.0557715 330 0.328924 0.0512711