New approach for measuring ||Vub|| at future B factories.

Measurement of the CKM Matrix Elements |Vcb | and |Vub | at the B-factories

JLAB-THY-02-19 ρ Polarization and ‘Model Independent ’ Extraction of |Vub|/|Vcd|

We briefly discuss the predictions of the heavy quark effective theory for the semileptonic decays of a heavy pseudoscalar to a light one, or to a light vector meson. We point out that measurement of combinations of differential helicity decay rates at Cleo-c and the B factories can provide a model independent means of extracting the ratio |Vub|/|Vcd|. We briefly discuss the corrections to this...

Semileptonic B Decays at the B Factories

Semileptonic B decays provide direct access to the CKM matrix elements Vub and Vcb, whose ratio gives a measurement of the side of the Unitarity Triangle opposite the angle β. The underlying theory of semileptonic B decays is at an advanced stage. The weak currents factorize in leptonic and hadronic parts which do not interact between each other. Moreover, the b quark mass is considerably large...

Measuring Arg ( V ub ) in B → Kπ

It has previously been shown that a measurement of Arg(Vub) = γ can be obtained from a triangle construction using B(B0 → K+π−), B(B̄0 → K−π+), B(B± → K0 sπ), and B(B± → π±π0). We evaluate experimental as well as theoretical uncertainties in this measurement. We find that a measurement of γ with the next generation B-factories (BaBar, BELLE, CLEO III) is statistics rather than theory limited if ...

|Vcb | and |Vub|: Theoretical Developments 1

Since sin 2β, the CP asymmetry in B → ψKS and related modes [1], is consistent with ǫK , |Vub|, and Bd,s mixing, searching for new flavor physics will require a combination of “redundant” and precise measurements that relate in the Standard Model (SM) to the same CKM elements. The determination of |Vcb| is important because the uncertainties in ǫK and in K → πνν̄ are proportional to |Vcb| , whil...