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arXiv · hep-ph/9712385

Four-jet angular distributions and color charge measurements: leading order versus next-to-leading order

Zoltan Nagy·Zoltan Trocsanyi
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Abstract

We present the next-to-leading order perturbative QCD prediction to the four-jet angular distributions used by experimental collaborations at LEP for measuring the QCD color charge factors. We compare our results to ALEPH data corrected to parton level. We perform a leading order ``measurement'' of the QCD color factor ratios by fitting the leading order perturbative predictions to the next-to-leading order result. Our result shows that in an experimental analysis for measuring the color charge factors the use of the O($α_s^3$) QCD predictions instead of the O($α_s^2$) results may shift the center of the fit by a relative factor of $1+2\as$ in the $T_R/C_F$ direction.

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Zoltan Nagy, Zoltan Trocsanyi. 1997-12-15. Four-jet angular distributions and color charge measurements: leading order versus next-to-leading order. https://doi.org/10.1103/physrevd.57.5793

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