Bonn 2010 – wissenschaftliches Programm
HK 67.1: Vortrag
Freitag, 19. März 2010, 14:00–14:15, JUR A
Quark-mass dependence of baryons in QCD with 2+1 flavors — •Thomas R. Hemmert and Andreas Schäfer — Institut für Theoretische Physik, Fakultät Physik, Universität Regensburg
Over the past few years the quark-mass dependence of baryon properties has been studied in detail via Lattice QCD simulations with 2 light quark flavors. For example, the observed quark-mass dependence of the mass of a nucleon is now well understood within the context of baryon chiral perturbation theory (ChPT), which can also correct for extra mass-shifts arising from the finite simulation volume .
Currently simulations with 2+1 quark-flavors are one of the frontier research areas in Lattice QCD studies of baryon structure (see e.g. [2,3]). However, all attempts to understand the observed quark-mass dependencies within the context of ChPT have failed so far, as the addition of a third flavor brings in several complications for the effective field theory of low energy QCD. In this talk we present new results  on the quark-mass dependencies of the masses of octet baryons. We also explain how we systematically overcome the previous problems of chiral extrapolation studies for baryon observables in the case of 2+1 quark flavors.
 e.g. see A. Ali Khan et al., Nucl. Phys. B689, 175 (2004).
 S. Dürr et al., Science 322, 1224 (2008).
 W. Bietenholz et al., PoS LAT2009:102 (2009).
 T.R. Hemmert and A. Schäfer, forthcoming.
This work has been supported by BMBF and DFG.