A Determination of electroweak parameters from Z0 ---> mu+ mu- (gamma)

We have measured the partial width and forward-backward charge asymmetry for the reaction e + e - →Z 0 →μ + μ - (γ). We obtain a partial width Γ μμ of 83.3±1.3(stat)±0.9(sys) MeV and the following values for the vector and axial vector couplings: g v =−0.062 −0.015 +0.020 and g A =−0.497 −0.005 +0.005 . From our measurement of the partial width and the mass of the Z 0 boson we determine the effective electroweak mixing angle, sin 2 θ w =0.232±0.005, and the neutral current coupling strength parameter, ϱ =0.998±0.016.

electron positron: colliding beams
colliding beams: electron positron
electron positron: annihilation
annihilation: electron positron
Z0: electroproduction
electroproduction: Z0
Z0: leptonic decay
leptonic decay: Z0
radiative correction
Z0: width

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Figures(0)

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