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arXiv · 2112.12767

Baryon masses from full QCD+QED${}_\text{C}$ simulations

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

In these proceedings we present preliminary results for the masses of the proton, neutron and $\Omega^-$ baryons obtained from QCD+QED lattice simulations performed with four dynamical quarks using C$^*$ boundary conditions. These results are part of the ongoing effort of the RC${}^*$ collaboration discussed in the companion proceedings, and have been obtained on a single ensemble in which the renormalised electromagnetic coupling is $\alpha_{\text{em}}\sim 0.04$, the physical volume is $L\sim 1.7$ fm and the masses of the four dynamical quarks have been tuned at the $U$--spin symmetric point $m_d=m_s$. We demonstrate on this unphysical ensemble that baryon masses can be calculated with satisfactory precision when including QED without the need for gauge--fixing and perturbation theory. This makes us confident in the effectiveness of the strategy presented here also in the case of simulations closer to the physical point.

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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. 2021-12-23. Baryon masses from full QCD+QED${}_\text{C}$ simulations. https://arxiv.org/abs/2112.12767

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