CLAS physics database search results Measurement E159M634 E1-6 V. Burkert 2001 theta(pi+) dsigma/d(−cos(theta_pip)) Stat. error deg mcb/rad mcb/rad 9 1.34789 0.259373 27 1.88662 0.310669 45 1.64514 0.280203 63 1.61462 0.247903 81 1.56611 0.240416 99 1.72927 0.257287 117 1.58294 0.242322 135 1.48947 0.399516 153 1.20515 0.828649 171 1.26887 0.951925