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arXiv · 2108.11989

An update on QCD+QED simulations with C* boundary conditions

Lucius Bushnaq·Isabel Campos·Marco Catillo·Alessandro Cotellucci·Madeleine Dale·Patrick Fritzsch·Jens Lücke·Marina Krstić Marinković·Agostino Patella·Nazario Tantalo
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Abstract

We present two novelties in our analysis of fully dynamical QCD+QED ensembles with C* boundary conditions. The first one is the explicit computation of the sign of the Pfaffian. We present an algorithm that provides a significant speedup compared to traditional methods. The second one is a reweighting of the mass in the context of the RHMC. We have tested the techniques on both pure QCD and QCD+QED ensembles with pions at $m_{\pi^\pm}\approx400$ MeV, a lattice spacing of $a\approx0.05$ fm, a fine-structure constant of $\alpha_{\mathrm{R}}=0$ and $0.04$.

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Lucius Bushnaq, Isabel Campos, Marco Catillo, Alessandro Cotellucci, Madeleine Dale, Patrick Fritzsch, Jens Lücke, Marina Krstić Marinković, Agostino Patella, Nazario Tantalo. 2021-08-26. An update on QCD+QED simulations with C* boundary conditions. https://arxiv.org/abs/2108.11989

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