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Behaviour of the topological susceptibility in two colour QCD across the finite density transition

B. Alles·M. D'Elia·M. P. Lombardo
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Abstract

The behaviour of the topological susceptibility χin QCD with two colours and 8 flavours of quarks is studied at nonzero temperature on the lattice across the finite density transition. It is shown that the signal of χdrops abruptly at a critical chemical potential μ_c, much as it happens at the finite temperature and zero density transition. The Polyakov loop and the chiral condensate undergo their transitions at the same critical value μ_c. At a value μ_s of the chemical potential, called saturation point, which in our case satisfies μ_s > μ_c, Pauli blocking supervenes and consequently the theory becomes quenched.

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B. Alles, M. D'Elia, M. P. Lombardo. 2006-06-23. Behaviour of the topological susceptibility in two colour QCD across the finite density transition. https://doi.org/10.1016/j.nuclphysb.2006.06.023

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