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arXiv · 1511.04914

Perturbative versus non-perturbative decoupling of heavy quarks

Francesco Knechtli·Mattia Bruno·Jacob Finkenrath·Björn Leder·Rainer Sommer
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Abstract

We simulate a theory with $N_f=2$ heavy quarks of mass $M$. At energies much smaller than $M$ the heavy quarks decouple and the theory can be described by an effective theory which is a pure gauge theory to leading order in $1/M$. We present results for the mass dependence of ratios such as $t_0(M)/t_0(0)$. We compute these ratios from simulations and compare them to the perturbative prediction. The latter relies on a factorisation formula for the ratios which is valid to leading order in $1/M$.

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Francesco Knechtli, Mattia Bruno, Jacob Finkenrath, Björn Leder, Rainer Sommer. 2015-11-16. Perturbative versus non-perturbative decoupling of heavy quarks. https://arxiv.org/abs/1511.04914

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