QCD lattice simulations with 2+1 flavours typically start at rather large up-down and strange quark masses and extrapolate first the strange quark mass to its physical value and then the up-down quark mass.
An alternative method of tuning the quark masses is discussed here in which the singlet quark mass is kept fixed, which ensures that the kaon always has mass less than the physical kaon mass.
It can also take into account the different renormalisations (for singlet and non-singlet quark masses) occurring for non-chirally invariant lattice fermions and so allows a smooth extrapolation to the physical quark masses.
This procedure enables a wide range of quark masses to be probed, including the case with a heavy up-down quark mass and light strange quark mass.
Tuning the strange quark mass in lattice simulations · Around
Built on
M. Lüscher, S. Sint, R. Sommer and P. Weisz, Nucl. Phys. B478
1996
Earlier work this paper cites.
A. Walker-Loud, Nucl. Phys. A747
2005
Earlier work this paper cites.
B. C. Tiburzi and A. Walker-Loud, Nucl. Phys. A748
2005
Earlier work this paper cites.
M. Göckeler, R. Horsley, A. C. Irving, D. Pleiter, P. E. L. Rakow, G. Schierholz and H. Stüben (QCDSF-UKQCD Collaborations) Phys. Lett. B639
2005
Earlier work this paper cites.
R. Edwards and B. Joó, Nucl. Phys. Proc. Suppl. 140