CLAS physics database search results Measurement E216M521 CLAS12 Run Group A Krishna Chandra 2018 theta(pi+) dsigma/d(−cos(theta_pip)) Stat. error Syst. error deg mcbn/rad mcbn/rad mcbn/rad 9 0.602216 0.077414 0.05174574 27 0.478202 0.0372102 0.04687454 45 0.486459 0.0287851 0.04164165 63 0.428352 0.0492628 0.03462152 81 0.399462 0.0222167 0.03088498 99 0.364955 0.0219494 0.02914851 117 0.350217 0.0282442 0.04243949 135 0.373826 0.0326147 0.08858882 153 0.388747 0.00755225 0.19814254 171 0.54734 0.00052925 0.28106015