Determinations of |Vub| with inclusive techniques at LEP

TL;DR

This paper reports on the measurement of the |Vub| element of the CKM matrix using inclusive semileptonic decay techniques at LEP, combining results from multiple experiments and theoretical predictions.

Contribution

It provides a new combined measurement of |Vub| from inclusive decay data at LEP, utilizing OPE predictions and multiple experimental results.

Findings

Measured charmless semileptonic branching fraction: 1.74 x 10^-3

Derived |Vub| value: (4.13 +0.42/-0.47) x 10^-3

Achieved improved precision in |Vub| determination

Abstract

The charmless semileptonic decay branching fraction has been measured, using inclusive techniques, by the Aleph, Delphi and L3 experiments at LEP. The average of their results is 1.74 +/- 0.37 +/- 0.38 +/- 0.21 10-3. From this result the value of the |Vub| element in the CKM mixing matrix has been derived, using OPE predictions, obtaining: |Vub| = (4.13 +0.42/-0.47 (stat.+det.) +0.43/-0.48 (b->c syst.) +0.24/-0.25 (b->u syst.) +/- 0.02 (taub) +/- 0.20 (HQE)) 10-3.