CLAS physics database search results Measurement E19M24 E89-004 R. A. Schumacher 2005 cos(theta) Cz Data errors dimensionless dimensionless dimensionless -0.7 1.019 0.603 -0.4 -0.344 0.869 -0.1 -0.064 0.565 0.2 -0.227 0.353 0.5 -0.442 0.257 0.8 -0.418 0.366