CLAS physics database search results Measurement E159M559 E1-6 V. Burkert 2001 psi(pi+) dsigma/dpsi_pip Stat. error deg mcb/rad mcb/rad 30 0.717686 0.102785 90 0.550562 0.077595 150 0.733563 0.10689 210 0.782019 0.106447 270 0.688115 0.101048 330 0.838992 0.117631