CLAS physics database search results Measurement E159M828 E1-6 V. Burkert 2001 psi(pi-) dsigma/dpsi_pim Stat. error deg mcb/rad mcb/rad 30 0.331346 0.0556578 90 0.357129 0.063373 150 0.374945 0.060242 210 0.398592 0.0626508 270 0.323209 0.049092 330 0.306912 0.0513684