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Next-to-leading-logarithmic QCD Corrections to the Cross Section sigma(e+e- to t bar t H) at 500 GeV

C. Farrell·A. H. Hoang
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Abstract

We determine the next-to-leading logarithmic (NLL) QCD corrections to the cross section sigma(e+e- to t bar t H) for center-of-mass energies up to 500 GeV. The dynamics is dominated by nonrelativistic effects, and the summation of terms singular in the relative t bar t velocity is mandatory to all orders in the strong coupling constant alpha_s using an effective theory. The summations lead to an enhancement of the tree level predictions by about a factor of two and are important for the determination of the top Yukawa coupling. We also study the impact of polarization of the electron-positron beams and provide a fast approximation formula for the known O(alpha_s) QCD fixed-order prediction.

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C. Farrell, A. H. Hoang. 2006-07-12. Next-to-leading-logarithmic QCD Corrections to the Cross Section sigma(e+e- to t bar t H) at 500 GeV. https://doi.org/10.1103/physrevd.74.014008

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