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arXiv · 2212.09578

$N_f = 1+2+1$ QCD+QED simulations with C$^\star$ boundary conditions

Anian Altherr·Lucius Bushnaq·Isabel Campos·Marco Catillo·Alessandro Cotellucci·Madeleine Dale·Patrick Fritzsch·Roman Gruber·Jens Lücke·Marina Krstić Marinković·Agostino Patella·Nazario Tantalo·Paola Tavella
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Abstract

We give an update on the ongoing effort of the RC$^\star$ collaboration to generate fully dynamical QCD+QED configurations with C$^\star$ boundary conditions using the openQ$^\star$D code. The simulations are tuned to the U-symmetric point ($m_d=m_s$) with pions at $m_{\pi^\pm}\approx 400$ MeV. The splitting of the light mesons is used as one of three tuning observables and fixed to $m_{K^0} - m_{K^\pm} \approx 5$ MeV and $m_{K^0} - m_{K^\pm} \approx 25$ MeV on ensembles with renormalized electromagnetic coupling $\alpha_\mathrm{R} \approx \alpha_\mathrm{phys.}$ and $\alpha_\mathrm{R}\approx 5.5 \alpha_\mathrm{phys.}$ respectively. We will discuss some details concerning our tuning strategy and present the calculation of the meson and baryon masses. Finally, we will also present a cost analysis for our simulations. More technical details on finite-volume effects and the tuning can be found in A. Cotellucci's proceedings.

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Anian Altherr, Lucius Bushnaq, Isabel Campos, Marco Catillo, Alessandro Cotellucci, Madeleine Dale, Patrick Fritzsch, Roman Gruber, Jens Lücke, Marina Krstić Marinković, Agostino Patella, Nazario Tantalo, Paola Tavella. 2022-12-19. $N_f = 1+2+1$ QCD+QED simulations with C$^\star$ boundary conditions. https://arxiv.org/abs/2212.09578

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