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$\mathit A{}^{(0,{{\mathit b}})}_{\mathit FB}$ CHARGE ASYMMETRY IN ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit b}}{{\overline{\mathit b}}}$

OUR FIT, which is obtained by a simultaneous fit to several ${{\mathit c}}$- and ${{\mathit b}}$-quark measurements as explained in the note “The ${{\mathit Z}}$ boson” and ref. LEP-SLC 2006, refers to the $\mathbf {{{\mathit Z}} pole}$ asymmetry. The experimental values, on the other hand, correspond to the measurements carried out at the respective energies.

ASYMMETRY ${\mathrm {(\%)}}$

STD. MODEL

$\sqrt {\mathit s }$ ${\mathrm {(GeV)}}$

DOCUMENT ID

TECN

$\bf{ 9.92 \pm0.16}$

OUR FIT

$ 9.58 \pm0.32 \pm0.14 $

$91.231$

DLPH

$ 10.04 \pm0.56 \pm0.25 $

$9.69$

$91.26$

DLPH

$ 9.72 \pm0.42 \pm0.15 $

$9.67$

$91.25$

OPAL

$ 9.77 \pm0.36 \pm0.18 $

$9.69$

$91.26$

OPAL

$ 9.52 \pm0.41 \pm0.17 $

$9.59$

$91.21$

ALEP

$ 10.00 \pm0.27 \pm0.11 $

$9.63$

$91.232$

ALEP

$ 7.62 \pm1.94 \pm0.85 $

$9.64$

$91.235$

DLPH

$ 9.60 \pm0.66 \pm0.33 $

$9.69$

$91.26$

L3

$ 9.31 \pm1.01 \pm0.55 $

$9.65$

$91.24$

L3

$ 9.4 \pm2.7 \pm2.2 $

$9.61$

$91.22$

OPAL

• • We do not use the following data for averages, fits, limits, etc. • •

$ 6.37 \pm1.43 \pm0.17 $

$5.8$

$89.449$

DLPH

$ 10.41 \pm1.15 \pm0.24 $

$12.1$

$92.990$

DLPH

$ 6.7 \pm2.2 \pm0.2 $

$5.7$

$89.43$

DLPH

$ 11.2 \pm1.8 \pm0.2 $

$12.1$

$92.99$

DLPH

$ 4.7 \pm1.8 \pm0.1 $

$5.9$

$89.51$

OPAL

$ 10.3 \pm1.5 \pm0.2 $

$12.0$

$92.95$

OPAL

$ 5.82 \pm1.53 \pm0.12 $

$5.9$

$89.50$

OPAL

$ 12.21 \pm1.23 \pm0.25 $

$12.0$

$92.91$

OPAL

$ -13.1 \pm13.5 \pm1.0 $

$3.2$

$88.38$

ALEP

$ 5.5 \pm1.9 \pm0.1 $

$5.6$

$89.38$

ALEP

$ -0.4 \pm6.7 \pm0.8 $

$7.5$

$90.21$

ALEP

$ 11.1 \pm6.4 \pm0.5 $

$11.0$

$92.05$

ALEP

$ 10.4 \pm1.5 \pm0.3 $

$12.0$

$92.94$

ALEP

$ 13.8 \pm9.3 \pm1.1 $

$12.9$

$93.90$

ALEP

$ 4.36 \pm1.19 \pm0.11 $

$5.8$

$89.472$

ALEP

$ 11.72 \pm0.97 \pm0.11 $

$12.0$

$92.950$

ALEP

$ 5.67 \pm7.56 \pm1.17 $

$5.7$

$89.434$

DLPH

$ 8.82 \pm6.33 \pm1.22 $

$12.1$

$92.990$

DLPH

$ 6.11 \pm2.93 \pm0.43 $

$5.9$

$89.50$

L3

$ 13.71 \pm2.40 \pm0.44 $

$12.2$

$93.10$

L3

$ 4.95 \pm5.23 \pm0.40 $

$5.8$

$89.45$

L3

$ 11.37 \pm3.99 \pm0.65 $

$12.1$

$92.99$

L3

$ -8.6 \pm10.8 \pm2.9 $

$5.8$

$89.45$

OPAL

$ -2.1 \pm9.0 \pm2.6 $

$12.1$

$93.00$

OPAL

$ -71 \pm34 {}^{+7}_{-8} $

$-58$

$58.3$

TOPZ

$ -22.2 \pm7.7 \pm3.5 $

$-26.0$

$35$

CELL

$ -49.1 \pm16.0 \pm5.0 $

$-39.7$

$43$

CELL

$ -28 \pm11 $

$-23$

$35$

TASS

$ -16.6 \pm7.7 \pm4.8 $

$-24.3$

$35$

JADE

$ -33.6 \pm22.2 \pm5.2 $

$-39.9$

$44$

JADE

$ 3.4 \pm7.0 \pm3.5 $

$-16.0$

$29.0$

MAC

$ -72 \pm28 \pm13 $

$-56$

$55.2$

AMY

¹	ABDALLAH 2005 obtain an enriched samples of ${{\mathit b}}{{\overline{\mathit b}}}$ events using lifetime information. The quark (or antiquark) charge is determined with a neural network using the secondary vertex charge, the jet charge and particle identification.

²

ABDALLAH 2004F tag ${{\mathit b}}-$ and ${{\mathit c}}-$quarks using semileptonic decays combined with charge flow information from the hemisphere opposite to the lepton. Enriched samples of ${{\mathit c}}{{\overline{\mathit c}}}$ and ${{\mathit b}}{{\overline{\mathit b}}}$ events are obtained using lifetime information.

³	ABBIENDI 2003P tag heavy flavors using events with one or two identified leptons. This allows the simultaneous fitting of the ${{\mathit b}}$ and ${{\mathit c}}~$quark forward-backward asymmetries as well as the average ${{\mathit B}^{0}}-{{\overline{\mathit B}}^{0}}$ mixing.

⁴	ABBIENDI 2002I tag ${{\mathit Z}^{0}}$ $\rightarrow$ ${{\mathit b}}{{\overline{\mathit b}}}$ decays using a combination of secondary vertex and lepton tags. The sign of the ${{\mathit b}}$-quark charge is determined using an inclusive tag based on jet, vertex, and kaon charges.

⁵	HEISTER 2002H measure simultaneously ${{\mathit b}}$ and ${{\mathit c}}$ quark forward-backward asymmetries using their semileptonic decays to tag the quark charge. The flavor separation is obtained with a discriminating multivariate analysis.

⁶

HEISTER 2001D tag ${{\mathit Z}}$ $\rightarrow$ ${{\mathit b}}{{\overline{\mathit b}}}$ events using the impact parameters of charged tracks complemented with information from displaced vertices, event shape variables, and lepton identification. The $\mathit b$-quark direction and charge is determined using the hemisphere charge method along with information from fast kaon tagging and charge estimators of primary and secondary vertices. The change in the quoted value due to variation of $\mathit A{}^{{{\mathit c}}}_{\mathit FB}$ and $\mathit R_{{{\mathit b}}}$ is given as $+0.103$ ($\mathit A{}^{{{\mathit c}}}_{\mathit FB}$ $-$ $0.0651$) $-0.440$ ($\mathit R_{{{\mathit b}}}$ $-$ $0.21585$).

⁷

ABREU 1999Y tag ${{\mathit Z}}$ $\rightarrow$ ${{\mathit b}}{{\overline{\mathit b}}}$ and ${{\mathit Z}}$ $\rightarrow$ ${{\mathit c}}{{\overline{\mathit c}}}$ events by an exclusive reconstruction of several ${{\mathit D}}~$ meson decay modes (${{\mathit D}^{*+}}$, ${{\mathit D}^{0}}$, and ${{\mathit D}^{+}}$ with their charge-conjugate states).

⁸

ACCIARRI 1999D tag ${{\mathit Z}}$ $\rightarrow$ ${{\mathit b}}{{\overline{\mathit b}}}$ events using high p and p$_{\mathit T}$ leptons. The analysis determines simultaneously a mixing parameter $\chi _{{{\mathit b}}}$ = $0.1192$ $\pm0.0068$ $\pm0.0051$ which is used to correct the observed asymmetry.

⁹	ACCIARRI 1998U tag ${{\mathit Z}}$ $\rightarrow$ ${{\mathit b}}{{\overline{\mathit b}}}$ events using lifetime and measure the jet charge using the hemisphere charge.

¹⁰	ALEXANDER 1997C identify the ${\mathit {\mathit b}}$ and ${\mathit {\mathit c}}$ events using a ${{\mathit D}}/{{\mathit D}^{*}}$ tag.

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