CLAS physics database search results Measurement E159M598 E1-6 V. Burkert 2001 theta(pi+) dsigma/d(−cos(theta_pip)) Stat. error deg mcb/rad mcb/rad 9 1.19532 0.234507 27 1.70861 0.289708 45 1.53498 0.258428 63 1.73804 0.26764 81 1.50462 0.226016 99 1.75116 0.255068 117 1.83437 0.280531 135 1.56392 0.389627 153 0.977821 0.669394 171 1.20673 0.915192