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arXiv · hep-ex/9907043

Determination of the LEP centre-of-mass energy from Zgamma events

ALEPH Collaboration
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Abstract

Radiative returns to the Z resonance (Zgamma events) are used to determine the LEP2 centre-of-mass energy from the data collected with the ALEPH detector in 1997. The average centre-of-mass energy is measured to be: E_CM = 182.50 +- 0.19(stat) +- 0.08(syst) GeV in good agreement with the precise determination by the LEP energy working group of 182.652 +- 0.050 GeV. If applied to the measurement of the W mass, its precision translates into a systematic error on M_W which is smaller than the statistical error achieved from the corresponding dataset.

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ALEPH Collaboration. 1999-07-21. Determination of the LEP centre-of-mass energy from Zgamma events. https://doi.org/10.1016/s0370-2693(99)00903-x

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