2022/07/20 by Bastian B. Brandt, Amine Chabane, Brandt, Bastian B. +9
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Lattice (hep-lat) #High-Energy Particle Collisions Research #Quantum Chromodynamics and Particle Interactions #Theoretical and Computational Physics
paper · pdf · doi:10.48550/arxiv.2207.10117
openalex publication_date 2022/07/20 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Imaginary chemical potentials serve as a useful tool to constrain the QCD phase diagram and to gain insight into the thermodynamics of strongly interacting matter. In this study, we report on the first determination of the phase diagram for arbitrary imaginary baryon and isospin chemical potentials at high temperature using one-loop perturbation theory, revealing a nontrivial structure of Roberge-Weiss (RW) phase transitions in this plane. Subsequently, this system is simulated numerically with N\rm f=2 unimproved staggered quarks on Nτ=4 lattices at a range of temperatures at one of the RW phase transitions. We establish a lower bound for the light quark mass, where the first-order transition line terminates in a tricritical point. It is found that this tricritical mass is increased as compared to the case of purely baryonic imaginary chemical potentials, indicating that our setup is more advantageous for identifying critical behavior towards the chiral limit. Finally, the dynamics of local Polyakov loop clusters is also studied in conjuction with the RW phase transition.