CLAS physics database search results Measurement E159M526 E1-6 V. Burkert 2001 theta(pi+) dsigma/d(−cos(theta_pip)) Data errors deg mcb/rad mcb/rad 9 1.15447 0.337041 27 1.39188 0.247277 45 1.56475 0.259005 63 1.41457 0.208445 81 1.41304 0.209018 99 1.36976 0.203961 117 1.37556 0.203751 135 1.34135 0.278143 153 0.95623 0.839917 171 0.775631 0.625851