Measurements of the B semileptonic branching fraction with lepton tags

We have used the CLEO II detector and 2.06fb−1 of ϒ(4S) data to measure the B-meson semileptonic branching fraction. The B→Xeν momentum spectrum was obtained over nearly the full momentum range by using charge and kinematic correlations in events with a high-momentum lepton tag and an additional electron. We find B(B→Xeν)=(10.49±0.17±0.43)%, with overall systematic uncertainties less than those of untagged single-lepton measurements. We use this result to calculate the magnitude of the Cabibbo-Kobayashi-Maskawa matrix element Vcb and to set an upper limit on the fraction of ϒ(4S) decays to final states other than BB¯.

electron positron: colliding beams
colliding beams: electron positron
electron positron: annihilation
annihilation: electron positron
Upsilon(10570): electroproduction
electroproduction: Upsilon(10570)
Upsilon(10570): hadronic decay
hadronic decay: Upsilon(10570)
B: pair production
pair production: B

References(18)

Figures(0)

The Baffling semileptonic branching ratio of B mesons

Ikaros I.Y. Bigi
(
- CERN and
- Notre Dame U.
)
,
Boris Blok
(
- Technion
)
,
Mikhail A. Shifman
(
- Minnesota U.
)
,
Arkady I. Vainshtein
(
- Minnesota U.
)

- Phys.Lett.B 323 (1994) 408-416
•
e-Print:
- hep-ph/9311339
•
DOI:
- 10.1016/0370-2693(94)91239-4

Inconclusive inclusive nonleptonic $B$ decays

- Phys.Rev.D 51 (1995) 1183-1191
•
e-Print:
- hep-ph/9405346
•
DOI:
- 10.1103/PhysRevD.51.1183

Theoretical update of the semileptonic branching ratio of B mesons

E. Bagan
(
- Barcelona, Autonoma U.
)
,
Patricia Ball
(
- Munich, Tech. U.
)
,
Vladimir M. Braun
(
- DESY
)
,
P. Gosdzinsky
(
- Barcelona, Autonoma U.
)

- Phys.Lett.B 342 (1995) 362-368,
- Phys.Lett.B 374 (1996) 363-364 (erratum)
•
e-Print:
- hep-ph/9409440
•
DOI:
- 10.1016/0370-2693(94)01410-E

QCD radiative enhancement of the decay b ---> c anti-c s

M.B. Voloshin
(
- Minnesota U. and
- Moscow, ITEP
)

- Phys.Rev.D 51 (1995) 3948-3951
•
e-Print:
- hep-ph/9409391
•
DOI:
- 10.1103/PhysRevD.51.3948

Measurements of semileptonic branching fractions of B mesons at the Upsilon (4S) resonance

CLEO

Collaboration

•

S. Henderson
(
- Harvard U.
)

et al.

- Phys.Rev.D 45 (1992) 2212-2231
•
DOI:
- 10.1103/PhysRevD.45.2212

A Model independent determination of the inclusive semileptonic decay fraction of B mesons

ARGUS

Collaboration

•

H. Albrecht
(
- DESY and
- DESY, Zeuthen
)

et al.

- Phys.Lett.B 318 (1993) 397-404
•
DOI:
- 10.1016/0370-2693(93)90146-9

The CLEO-II detector

CLEO

Collaboration

•

Y. Kubota
(
- Minnesota U.
)

et al.

- Nucl.Instrum.Meth.A 320 (1992) 66-113
•
DOI:
- 10.1016/0168-9002(92)90770-5

Semileptonic B and D Decays in the Quark Model

- Phys.Rev.D 39 (1989) 799-818
•
DOI:
- 10.1103/PhysRevD.39.799

Measurement of the inclusive B ---> tau-neutrino X branching ratio

L3

Collaboration

•

M. Acciarri

et al.

- Phys.Lett.B 332 (1994) 201-208
•
DOI:
- 10.1016/0370-2693(94)90880-X

Measurement of the b ---> tau- anti-tau-neutrino X branching ratio and an upper limit on B- ---> tau- anti-tau-neutrino

ALEPH

Collaboration

•

D. Buskulic
(
- Annecy, LAPP
)

et al.

- Phys.Lett.B 343 (1995) 444-452
•
DOI:
- 10.1016/0370-2693(94)01584-Y

A New determination of the $B^0$ - $\bar{B}^0$ oscillation strength

ARGUS

Collaboration

•

H. Albrecht
(
- DESY
)

et al.

- Z.Phys.C 55 (1992) 357-364

Two measurements of B0 anti-B0 mixing

CLEO

Collaboration

•

John E. Bartelt
(
- Vanderbilt U.
)

et al.

- Phys.Rev.Lett. 71 (1993) 1680-1684,
- Phys. Rev. Lett. 71 (1993) 1680-1684 and Cornell Univ. Ithaca - CLNS-93-1207 (93/04,rec.May) 9 p
•
DOI:
- 10.1103/PhysRevLett.71.1680