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arXiv · hep-ex/0402001

Measurement of the Z-boson using e+e- -> Z gamma events at centre-of-mass energies above the Z pole

L3 Collaboration
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Abstract

Events from the e+e- -> Zgamma process with hard initial state radiation collected with the L3 detector at centre-of-mass energies between 183 GeV and 209 GeV are used to measure the mass of the Z boson. Decays of the Z boson into hadrons or muon pairs are considered and the Z mass is determined to be 91.272 +- 0.032 (stat.) +- 0.033 (syst.) GeV, in agreement with the value measured at the Z resonance. Alternatively, assuming this measured value of the Z mass, the method determines the LEP beam energy, found to be 87 +- 34 (stat.) \pm 34 (syst.) MeV lower than the nominal value.

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L3 Collaboration. 2004-01-31. Measurement of the Z-boson using e+e- -> Z gamma events at centre-of-mass energies above the Z pole. https://doi.org/10.1016/j.physletb.2004.01.074

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