2016/10/31 by Owe Philipsen, Philipsen, Owe, Alessandro Sciarra +1
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 #hep-lat
paper · pdf · doi:10.48550/arxiv.1610.09979
7 pages, 3 figures, proceedings of the 34th International Symposium on Lattice Field Theory (Lattice 2016), 24-30 July 2016, Southampton, UK
arxiv created 2016/10/31 · openalex publication_date 2016/10/31 · arxiv updated 2016/11/01 · openalex created_date 2022/10/04 · openalex updated_date 2026/07/28
The QCD phase diagram at imaginary chemical potential exhibits a rich structure and studying it can constrain the phase diagram at real values of the chemical potential. Moreover, at imaginary chemical potential standard numerical techniques based on importance sampling can be applied, since no sign problem is present. In the last decade, a first understanding of the QCD phase diagram at purely imaginary chemical potential has been developed, but most of it is so far based on investigations on coarse lattices (Nτ=4, a=0.3 fm). Considering the Nf=2 case, at the Roberge-Weiss critical value of the imaginary chemical potential, the chiral/deconfinement transition is first order for light/heavy quark masses and second order for intermediate values of the mass: there are then two tricritical masses, whose position strongly depends on the lattice spacing and on the discretization. On Nτ=4, we have the chiral mπtric.=400 MeV with unimproved staggered fermions and mπtric.\gtrsim900 MeV with unimproved pure Wilson fermions. Employing finite size scaling we investigate the change of this tricritical point between Nτ=4 and Nτ=6 as well as between Wilson and staggered discretizations.