CLAS physics database search results Measurement E159M28 E1-6 V. Burkert 2001 psi(pi+) dsigma/dpsi_pip Data errors deg mcb/rad mcb/rad 30 0.442935 0.0718547 90 0.378097 0.0649675 150 0.619617 0.0947785 210 0.568911 0.0889966 270 0.405057 0.0644765 330 0.435103 0.0703905