Open-boundary conditions in the deconfined phase

In this work, we consider open-boundary conditions at high temperatures, as they can potentially be of help to measure the topological susceptibility. In particular, we measure the extent of the boundary effects at [Formula: see text] and [Formula: see text] . In the first case, it is larger than at [Formula: see text] while we find it to be smaller in the second case. The length of this “boundary zone” is controlled by the screening masses. We use this fact to measure the scalar and pseudo-scalar screening masses at these two temperatures. We observe a mass gap at [Formula: see text] but not at [Formula: see text] . Finally, we use our pseudo-scalar channel analysis to estimate the topological susceptibility. The results at [Formula: see text] are in good agreement with the literature. At [Formula: see text] , they appear to suffer from topological freezing, which prevents us from providing a precise determination of the topological susceptibility.