Measuring Mass Splittings in Baryon SU(2) Multiplets

Abstract

The inclusion of isospin-breaking corrections arising from electromagnetic interactions and the up-down quark mass difference is becoming increasingly important in lattice QCD calculations, as the precision of observables is at or approaching the percent level. In this context, the RM123 method has been employed in recent years to take into account such isospin corrections. In this work, we study baryon mass splittings using the RM123 approach. Preliminary results are presented for the mass splittings within spin-1/2 and spin-3/2 baryon SU(2) multiplets, obtained using twisted-mass ensembles tuned close to physical quark masses. We consider only valence contributions, with the splittings computed at leading order in the isospin-breaking parameters.