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arXiv · 2602.10921

Dirac mode localization in QCD near the crossover temperature

Matteo Giordano·Tamas G. Kovacs·Ferenc Pittler
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Abstract

We study the localization properties of the low-lying Dirac eigenmodes in QCD near the crossover temperature, using stout-smeared staggered fermions and Symanzik-improved gauge action on the lattice. On $N_{\mathrm{t}}=8$ lattices we find that localized low modes, absent at low temperature, appear at a temperature $T_{\mathrm{loc}}$ in the range $150\,\mathrm{MeV}\le T_{\mathrm{loc}}\le 160\,\mathrm{MeV}$, well within the chiral crossover range as determined from the chiral condensate and from the light-quark susceptibility. Since with our choice of lattice action neither the chiral transition region nor the renormalized mobility edges change significantly above $N_{\mathrm{t}}=8$, our conclusion that $T_{\mathrm{loc}}$ is in the chiral crossover region is expected to remain valid in the continuum limit.

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Matteo Giordano, Tamas G. Kovacs, Ferenc Pittler. 2026-02-11. Dirac mode localization in QCD near the crossover temperature. https://arxiv.org/abs/2602.10921

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