An improved measurement of the forward-backward asymmetry in Z --> b (b) over bar decays is presented, based on a sample of 4.1 million hadronic Z decays collected by ALEPH between 1991 and 1995. Data are analysed as a function of polar angle of the event axis and b purity. The event tagging efficiency and mean b-jet hemisphere charge are measured directly from data. From the measured forward-backward jet charge asymmetry, the b quark asymmetry at root s= m(Z) is determined to be: A(FB)(b) = 0.1017 +/- 0.0032(syst.) +/- 0.0032(syst.). In the context of the Standard Model this corresponds to a value of the effective weak mixing angle of sin(2)theta(W)(eff)= 0.23109 +/- 0.00096.

R., B., D., B., D., D., P., G., C., C., J. P., L., et al. (1998). Determination of A(FB)(b) using jet charge measurements in Z decays. PHYSICS LETTERS. SECTION B, 426(1-2), 217-230 [10.1016/S0370-2693(98)00345-1].

Determination of A(FB)(b) using jet charge measurements in Z decays

CIOCCI, MARIA AGNESE;MARROCCHESI, PIER SIMONE;
1998-01-01

Abstract

An improved measurement of the forward-backward asymmetry in Z --> b (b) over bar decays is presented, based on a sample of 4.1 million hadronic Z decays collected by ALEPH between 1991 and 1995. Data are analysed as a function of polar angle of the event axis and b purity. The event tagging efficiency and mean b-jet hemisphere charge are measured directly from data. From the measured forward-backward jet charge asymmetry, the b quark asymmetry at root s= m(Z) is determined to be: A(FB)(b) = 0.1017 +/- 0.0032(syst.) +/- 0.0032(syst.). In the context of the Standard Model this corresponds to a value of the effective weak mixing angle of sin(2)theta(W)(eff)= 0.23109 +/- 0.00096.
1998
R., B., D., B., D., D., P., G., C., C., J. P., L., et al. (1998). Determination of A(FB)(b) using jet charge measurements in Z decays. PHYSICS LETTERS. SECTION B, 426(1-2), 217-230 [10.1016/S0370-2693(98)00345-1].
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11365/37835
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