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Study of the Decoupling of Heavy Fermions in a Z_2 Scalar-Fermion Model

Lee Lin
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Abstract

According to one-loop perturbation theory, fermions whose masses are totally generated from Yukawa couplings do not decouple in the heavy mass limit. We investigate this issue nonperturbatively in a 4-dimensional $Z_2$ scalar-fermion model with staggered fermions. Our data at intermediate and stronger Yukawa couplings on $8^4$ and $12^4$ lattices suggest the nondecoupling of heavy fermions as predicted from one-loop calculation. However, at the strongest Yukawa coupling where a possible multi-critical point may come into play, we cannot be conclusive.

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BibTeXRIS

Lee Lin. 1995-01-19. Study of the Decoupling of Heavy Fermions in a Z_2 Scalar-Fermion Model. https://doi.org/10.1016/0370-2693(95)00065-s

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