Direct measurement of leptonic coupling asymmetries with polarized Z's.

The SLD collaboration Abe, K. ; Akagi, T. ; Allen, N.J. ; et al.
Phys.Rev.Lett. 79 (1997) 804-808, 1997.
Inspire Record 442260 DOI 10.17182/hepdata.19552

We present direct measurements of the $Z~0$-lepton coupling asymmetry parameters, $A_e$, $A_\mu$, and $A_\tau$, based on a data sample of 12,063 leptonic $Z~0$ decays collected by the SLD detector. The $Z$ bosons are produced in collisions of beams of polarized $e~-$ with unpolarized $e~+$ at the SLAC Linear Collider. The couplings are extracted from the measurement of the left-right and forward-backward asymmetries for each lepton species. The results are: $A_e=0.152 \pm 0.012 {(stat)} \pm 0.001 {(syst)}$, $A_\mu=0.102 \pm 0.034 \pm 0.002$, and $A_\tau=0.195 \pm 0.034 \pm 0.003$.

1 data table match query

No description provided.


Search for a Z-prime at the Z resonance

The L3 collaboration Adriani, O. ; Aguilar-Benitez, M. ; Ahlen, S.P. ; et al.
Phys.Lett.B 306 (1993) 187-196, 1993.
Inspire Record 355489 DOI 10.17182/hepdata.28919

The search for an additional heavy gauge boson Z′ is described. The models considered are based on either a superstring-motivated E 6 or on a left-right symmetry and assume a minimal Higgs sector. Cross sections and asymmetries measured with the L3 detector in the vicinity of the Z resonance during the 1990 and 1991 running periods are used to determine limits on the Z-Z′ gauge boson mixing angle and on the Z′ mass. For Z′ masses above the direct limits, we obtain the following allowed ranges of the mixing angle, θ M at the 95% confidence level: −0.004 ⪕ θ M ⪕ 0.015 for the χ model, −0.003 ⪕ θ M ⪕ 0.020 for the ψ model, −0.029 ⪕ θ M ⪕ 0.010 for the η model, −0.002 ⪕ θ M ⪕ 0.020 for the LR model,

2 data tables match query

Data taken during 1990.

Data taken during 1991.


A MEASUREMENT OF THE Z0 LEPTONIC PARTIAL WIDTHS AND THE FORWARD - BACKWARD ASYMMETRY

The L3 collaboration Adeva, B. ; Adriani, O. ; Aguilar-Benitez, M. ; et al.
L3-005, 1990.
Inspire Record 294576 DOI 10.17182/hepdata.29691

None

1 data table match query

No description provided.


Measurement of cross-sections and leptonic forward - backward asymmetries at the z pole and determination of electroweak parameters

The L3 collaboration Acciarri, M. ; Adam, A. ; Adriani, O. ; et al.
Z.Phys.C 62 (1994) 551-576, 1994.
Inspire Record 374696 DOI 10.17182/hepdata.48198

We report on the measurement of the leptonic and hadronic cross sections and leptonic forward-backward asymmetries at theZ peak with the L3 detector at LEP. The total luminosity of 40.8 pb−1 collected

12 data tables match query

Results from 1990 data. Additional systematic uncertainty of 0.005.. Acollinearity required to be <15 degrees.

Results from 1991 data. Additional systematic uncertainty of 0.002.. Acollinearity required to be <15 degrees.

Results from 1992 data. Additional systematic uncertainty of 0.002.. Acollinearity required to be <15 degrees.

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