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arXiv · 1111.2319

The chiral phase transition for QCD with sextet quarks

D. K. Sinclair·J. B. Kogut
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Abstract

QCD with 2 massless colour-sextet quarks is studied as a model of Walking Technicolor. We simulate lattice QCD with 2 light color-sextet staggered quarks at finite temperature, and use the dependence of the coupling at the chiral transition on the temporal extent, $N_t$, of the lattice in lattice units to study the running of the bare lattice coupling with lattice spacing. Our goal is to determine whether this theory is QCD-like and `walks', or if it is conformal. If it is QCD-like, the coupling at the chiral transition should tend to zero as $N_t \rightarrow \infty$ in a manner controlled by asymptotic freedom, i.e. by the perturbative $\beta$-function. On the other hand, if this theory is conformal, this coupling will approach a non-zero limit in the $N_t \rightarrow \infty$ limit. We are extending our simulations on an $N_t=8$ lattice to determine the position of the chiral transition with greater accuracy, and are performing simulations on an $N_t=12$ lattice.

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D. K. Sinclair, J. B. Kogut. 2011-11-09. The chiral phase transition for QCD with sextet quarks. https://arxiv.org/abs/1111.2319

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