Measurement of the b forward-backward asymmetry and mixing using high-p⊥ leptons

Buskulic, D.; De Bonis, I.; Decamp, D.; Ghez, Philippe; Goy, C.; Lees, J.-P.; Lucotte, A.; Minard, M.-N.; Odier, P.; Pietrzyk, B.

doi:10.1016/0370-2693(96)00926-4

Measurement of the b forward-backward asymmetry and mixing using high-p⊥ leptons

ALEPH

Collaboration

May, 1996

13 pages

Published in:

Phys.Lett.B 384 (1996) 414-426,
Phys.Lett.B 384 (1996) 414-426

Published: Feb 12, 1999

DOI:

10.1016/0370-2693(96)00926-4 (publication)

Report number:

CERN-PPE-96-072,
CERN-PPE-96-72

Experiments:

CERN-LEP-ALEPH

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Abstract: (Elsevier B.V.)

The B⁰ - B̄⁰ average mixing parameter

χ

and b forward-backward asymmetry AFB⁰(b) are measured from a sample of about 4 200 000 Z → qq̄ events recorded with the ALEPH detector at LEP in the years 1990–1995. High transverse momentum electrons and muons produced in b semileptonic decays provide the tag of the quark flavour and of its charge. The average mixing parameter and the pole b asymmetry are measured to be

χ

= 0.1246 ± 0.0051stat ± 0.0052syst, AFB⁰(b) = 0.1008 ± 0.0043stat ± 0.0028syst. The value of sin²θw^eff = 0.23198 ± 0.00092 is extracted from the asymmetry measurement.

electron positron: colliding beams
electron positron: annihilation
Z0: electroproduction
Z0: hadronic decay
bottom: pair production
bottom: semileptonic decay
B0 anti-B0: mixing
angular distribution: asymmetry
particle identification: flavor
lepton: transverse momentum

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Figures(0)

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