O(2)-scaling in finite and infinite volume

Paul Springer; Bertram Klein

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arXiv · 1506.00909

O(2)-scaling in finite and infinite volume

Paul Springer·Bertram Klein

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Abstract

The exact nature of the chiral phase transition in QCD is still under investigation. In $N_f=2$ and $N_f=(2+1)$ lattice simulations with staggered fermions the expected O($N$)-scaling behavior was observed. However, it is still not clear whether this behavior falls into the O(2) or O(4) universality class. To resolve this issue, a careful scaling and finite-size scaling analysis of the lattice results is needed. We use a functional renormalization group to perform a new investigation of the finite-size scaling regions in O(2)- and O(4)-models. We also investigate the behavior of the critical fluctuations by means of the $4^{\text{th}}$-order Binder cumulant. The finite-size analysis of this quantity provides an additional way for determining the universality class of the chiral phase transition in lattice QCD.

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Paul Springer, Bertram Klein. 2015-06-02. O(2)-scaling in finite and infinite volume. https://arxiv.org/abs/1506.00909

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