CLAS physics database search results Measurement E159M220 E1-6 V. Burkert 2001 theta(pi+) dsigma/d(−cos(theta_pip)) Data errors deg mcb/rad mcb/rad 9 5.26173 0.943536 27 4.43641 0.75781 45 3.63607 0.611335 63 3.49156 0.530856 81 3.29519 0.506359 99 3.56779 0.558602 117 3.256 0.506509 135 3.95532 0.989247 153 2.06008 1.28717 171 1.88195 1.319