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Study of prompt photon production in hadronicZ 0 decays

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Zeitschrift für Physik C Particles and Fields

Abstract

From a sample of 1.5 millionZ 0qq decays collected by the DELPHI detector during 1991, 1992 and 1993, the production cross section for isolated final state photons is measured and is compared with theO(α, α s) matrix element calculations implemented in the EEPRAD and GNJETS Monte Carlo generators. The observed photon yield is used to derive the electroweak couplings of charge 2/3 (u-type) and charge 1/3 (d-type) quarks to theZ 0 boson. The measured valuesc 2/3=0.91 +0.25−0.36 andc 1/3=1.62 +0.24−0.17 are compatible with the Standard Model prediction,c 2/3=1.145 andc 1/3=1.477.

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DELPHI Collaboration., Abreu, P., Adam, W. et al. Study of prompt photon production in hadronicZ 0 decays. Z. Phys. C - Particles and Fields 69, 1–13 (1995). https://doi.org/10.1007/BF02907381

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  • DOI: https://doi.org/10.1007/BF02907381

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