New measurements of the D→μν form factor ratios

Abstract

Using a large sample of D+→K−π+μ+ν decays collected by the FOCUS photoproduction experiment at Fermilab, we present new measurements of two semileptonic form factor ratios: rv and r2. We find rv=1.504±0.057±0.039 and r2=0.875±0.049±0.064. Our form factor results include the effects of the s-wave interference discussed in Phys. Lett. B 535 (2002) 43.