CLAS physics database search results Measurement E18M30 E89-004 R. A. Schumacher 2005 cos(theta) Cz Data errors dimensionless dimensionless dimensionless -0.75 0.907 0.402 -0.55 1.412 0.416 -0.35 1.025 0.472 -0.15 0.932 0.429 0.05 0.866 0.317 0.25 0.499 0.293 0.45 1.439 0.17 0.65 0.508 0.386 0.85 0.36 0.172