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arXiv · 1012.2230

Universal critical behavior and the transition temperature in (2+1)-flavor QCD

Christian Schmidt
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Abstract

We discuss the universal critical behavior in (2+1)-flavor QCD by analyzing lattice data from improved staggered fermions generated by the HotQCD Collaboration. We present recent results from two different lattice discretizations and various lattice spacings ($N_\tau=6,8,12$) at fixed physical strange quark mass ($m_s$) but varying light quark mass ($m_l$). We find that the chiral order-parameter, i.e. the chiral condensate, shows the expected universal scaling that is associated with the critical point in the chiral limit already for light quark masses $m_l/m_s \lsim 0.05$. From an analysis of the disconnected chiral susceptibility we estimate a preliminary value of the QCD transition temperature.

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Christian Schmidt. 2010-12-10. Universal critical behavior and the transition temperature in (2+1)-flavor QCD. https://doi.org/10.1063/1.3575079

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