Determination of the LEP Beam Energy using Radiative Fermion-pair Events

The OPAL collaboration; G. Abbiendi

doi:10.1016/j.physletb.2004.10.046

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arXiv · hep-ex/0408130

Determination of the LEP Beam Energy using Radiative Fermion-pair Events

The OPAL collaboration·G. Abbiendi

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Abstract

We present a determination of the LEP beam energy using "radiative return" fermion-pair events recorded at centre-of-mass energies from 183 GeV to 209 GeV. We find no evidence of a disagreement between the OPAL data and the LEP Energy Workings Group's standard calibration. Including the energy- averaged 11 MeV uncertainty in the standard determination, the beam energy we obtain from the OPAL data is higher than that obtained from the LEP calibration by 0+-34(stat.)+-27(syst.)MeV

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The OPAL collaboration, G. Abbiendi. 2004-08-25. Determination of the LEP Beam Energy using Radiative Fermion-pair Events. https://doi.org/10.1016/j.physletb.2004.10.046

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