Measurements of the q2 dependence of the D0→K−μ+ν and D0→π−μ+ν form factors

Abstract Using a large sample of D 0 → K − μ + ν and D 0 → π − μ + ν decays collected by the FOCUS photoproduction experiment at Fermilab, we present new measurements of the q 2 dependence for the f + ( q 2 ) form factor. These measured f + ( q 2 ) form factors are fit to common parameterizations such as the pole dominance form and compared to recent unquenched Lattice QCD calculations. We find m pole = 1.93 ± 0.05 ± 0.03 GeV / c 2 for D 0 → K − μ + ν and m pole = 1.91 −0.15 +0.30 ± 0.07 GeV / c 2 for D 0 → π − μ + ν and f − ( K ) ( 0 ) / f + ( K ) ( 0 ) = − 1.7 −1.4 +1.5 ± 0.3 .