CLAS physics database search results Measurement E46M149 N/A 0 cos(theta_HS^pi+) dsigma/dcos(theta_HS^pi+) Data errors dimensionless mcb mcb -0.875 0.47882 0.224449 -0.625 0.148151 0.053984 -0.375 0.128542 0.041268 -0.125 0.115379 0.044172 0.125 0.114961 0.041783 0.375 0.149967 0.048007