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arXiv · 0909.2019

QCD thermodynamics with colour-sextet quarks

D. K. Sinclair·J. B. Kogut
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Abstract

We study QCD with two flavours of colour-sextet quarks as a candidate walking-Technicolor theory. We simulate lattice QCD with two flavours of colour-sextet staggered quarks at finite temperatures to observe the scales of confinement and chiral-symmetry breaking. These should give us some indication as to whether the massless theory has an infrared fixed point making it a conformal field theory, or whether it exhibits confinement and chiral symmetry breaking with a slowly varying coupling constant, i.e. `walks'. We find that unlike the case with fundamental quarks, the deconfinement and chiral-symmetry restoration transitions are far apart. The values of $\beta=6/g^2$ for both transitions increase when $Ta$ is decreased from 1/4 to 1/6 as would be expected for finite temperature transitions of an asymptotically-free field theory. So far we see no suggestion of conformal behaviour.

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D. K. Sinclair, J. B. Kogut. 2009-09-10. QCD thermodynamics with colour-sextet quarks. https://arxiv.org/abs/0909.2019

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