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arXiv · hep-lat/9304001

Heavy Dynamical Fermions in Lattice QCD

Anna Hasenfratz·Thomas A. DeGrand
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Abstract

It is expected that the only effect of heavy dynamical fermions in QCD is to renormalize the gauge coupling. We derive a simple expression for the shift in the gauge coupling induced by $N_f$ flavors of heavy fermions. We compare this formula to the shift in the gauge coupling at which the confinement-deconfinement phase transition occurs (at fixed lattice size) from numerical simulations as a function of quark mass and $N_f$. We find remarkable agreement with our expression down to a fairly light quark mass. However, simulations with eight heavy flavors and two light flavors show that the eight flavors do more than just shift the gauge coupling. We observe confinement-deconfinement transitions at $β=0$ induced by a large number of heavy quarks. We comment on the relevance of our results to contemporary simulations of QCD which include dynamical fermions.

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Anna Hasenfratz, Thomas A. DeGrand. 1993-04-01. Heavy Dynamical Fermions in Lattice QCD. https://doi.org/10.1103/physrevd.49.466

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