Sie befinden Sich nicht im Netzwerk der Universität Paderborn. Der Zugriff auf elektronische Ressourcen ist gegebenenfalls nur via VPN oder Shibboleth (DFN-AAI) möglich. mehr Informationen...
Isospin splittings of meson and baryon masses from three-flavor lattice QCD $+$ QED
Ort / Verlag
Deutsches Elektronen-Synchrotron, DESY, Hamburg
Erscheinungsjahr
2016
Link zum Volltext
Quelle
Alma/SFX Local Collection
Beschreibungen/Notizen
Lattice QCD simulations are now reaching a precision where isospin breaking effects become important. Previously, we have developed a program to systematically investigate the pattern of flavor symmetry beaking within QCD and successfully applied it to meson and baryon masses involving up, down and strange quarks. In this Letter we extend the calculations to QCD + QED and present our first results on isospin splittings in the pseudoscalar meson and baryon octets. In particular, we obtain the nucleon mass difference of ${M}_{n}-{M}_{p}=1.35(18)(8){\rm{MeV}}$ and the electromagnetic contribution to the pion splitting ${M}_{{\pi }^{+}}-{M}_{{\pi }^{0}}=4.60(20){\rm{MeV}}$. Further we report first determination of the separation between strong and electromagnetic contributions in the $\overline{\mathrm{MS}}$ scheme.