CLAS physics database search results Measurement E159M171 E1-6 V. Burkert 2001 psi(pi-) dsigma/dpsi_pim Stat. error deg mcb/rad mcb/rad 30 0.879849 0.125707 90 1.00581 0.142883 150 1.19632 0.168916 210 1.22265 0.177298 270 0.984632 0.139018 330 0.930199 0.133982