29aSN-3 Measurement of B^+→ω1^+v

抄録

The magnitude of the Cabibbo-Kobayashi-Maskawa (CKM) matrix element V_<ub>, which is known still with large experimental uncertainty, can be determined from exclusive semileptonic transitions B→X_u1v. So far, the decays B→π1v and B→p1v have been observed by the CLEO experiment. In this talk, we will present a search for the decay B^+→ω1^+v. based on a sample of 85 million Y(4S)→BB^^^- events recorded with the Belle detector at the KEKB e^+e^- storage ring.