ISSN - 00319007, EISSN - 10797114, Physical Review Letters, 2006, vol. 97, p. -
Measurement of D0→πlν(Klν) form factors and absolute branching fractions
Using a 282fb-1 data sample collected by the Belle experiment at the KEKB e+e- collider, we study D0 decays to K-+ν and π-+ν final states. The D0 flavor and momentum are tagged through a full reconstruction of the recoiling charm meson and additional mesons from fragmentation. The reconstruction method provides very good resolution in neutrino momentum and in q2=(p+pν)2. Normalizing to the total number of D0 tags, we measure the absolute branching fractions to be B(D0→Kν)=(3.45±0.07stat±0.20syst)% and B(D0→πν)=(0.255±0.019stat±0.016syst)% and the semileptonic form factors (within the modified pole model) f+K(0)=0. 695±0.007stat±0.022syst and f+π(0)=0.624±0. 020stat±0.030syst. © 2006 The American Physical Society.