arXiv subjects

P. Thomas Jahn

Publications and source records attributed to P. Thomas Jahn.

4 recordsLinked to original sources

arXiv2021

Multicanonical reweighting for the QCD topological susceptibility

We introduce a reweighting technique which allows for a continuous sampling of temperatures in a single simulation and employ it to compute the temperature dependence of the QCD topological susceptibility at high temperatures. The method determines the ratio of susceptibility between any two temperatures within the explored temperature range. We find that the results from the method agree with our previous determination and that it is competitive with but not better than existing methods of determining the temperature derivative of the susceptibility. The method may also be useful in exploring the temperature dependence of other thermodynamical observables in QCD in a continuous way.

hep-lat↗

arXiv2020

Improved Reweighting for QCD Topology at High Temperature

In a previous paper \cite{Jahn:2018dke} we presented a methodology for computing the topological susceptibility of QCD at temperatures where it is small and standard methods fail. Here we improve on this methodology by removing two barriers to the reweighting method's moving between topological sectors. We present high-statistics, continuum-extrapolated results for the susceptibility of pure-glue QCD up to $7 T_c$. We show that the susceptibility varies with temperature as $T^{-6.7\pm 0.3}$ between $T=2.5 T_c$ and $T=7 T_c$, in good agreement with expectations based on the dilute instanton gas approximation.

hep-lat↗

arXiv2018

Topological Susceptibility to High Temperatures via Reweighting

We measure the topological susceptibility of quenched QCD on the lattice at two high temperatures. For this, we define topology with the help of gradient flow and mitigate the statistical problem of topology at high temperatures using a reweighting technique. This allows us to enhance tunneling events between topological sectors and alleviate topological freezing. We quote continuum extrapolated results for the susceptibility at $2.5$ and $4.1~T_\mathrm c$ that agree well with the existing literature. We conclude that the method is feasible and can be extended to unquenched QCD with no conceptual problems.

hep-lat↗

arXiv2018

$χ_{\textrm{top}}(T \gg T_{\textrm{c}})$ in pure-glue QCD through reweighting

We calculate the topological susceptibility at 2.5 Tc and 4.1 Tc in SU(3) pure Yang-Mills theory. We define topology with the help of gradient flow and we largely overcome the problem of poor statistics at high temperatures by applying a reweighting technique in terms of the topological charge, measured after a specific small amount of gradient flow. This allows us to obtain a sample of configurations which compares topological sectors with good statistics, with enhanced tunneling between topologies. We quote continuum extrapolated results at these two temperatures and conclude that our method is viable and can be extended without new conceptual problems to the case of full QCD with fermions.

hep-lat↗