Lattice2010

Session

Parallel 33: Hadron spectroscopy

15 Jun 2010, 14:30

Villasimius, Sardinia

97. 2+1 flavor DWF QCD and almost physical pion masses

Robert Mawhinney (Columbia University)

15/06/2010, 14:30

Hadron spectroscopy

We are producing 2+1 flavor DWF ensembles with dynamical pion masses of 180 and 250 MeV, a volume of (4.5 fm)^3 and 1/a = 1.4 GeV, using the Iwasaki plus DSDR (Dislocation Suppressing Determinant Ratio) gauge action. Basic properties of these ensembles and their production are discussed. We report on measurements of pseudoscalar masses and decay constants on these ensembles,...

184. Strange quark content of nucleon via reweighting on (2+1)-flavor Domain Wall Fermion lattices

Chulwoo Jung (Brookhaven National Laboratory)

15/06/2010, 14:50

Hadron spectroscopy

The slope of nucleon mass with respect to the dynamical strange quark mass is directly related to the strange quark content of nucleon ($\langle N | \bar{s}s | N \rangle $). This slope can be calcuated by shifting of dynamical strange quark mass via reweighting on dynamical ensembles, which allows a relatively inexpensive evaluation of the quantity without direct evaluation of...

240. Sigma term and strange content of the nucleon

Alberto Ramos (Centre de Physique Theorique, Marseille (CNRS))

15/06/2010, 15:10

Hadron spectroscopy

The sigma term and strange content of the nucleon play an important role in hadronic physics and dark matter detection. Preliminary results for these quantities, obtained from 2+1 flavor lattice QCD simulations, will be presented. Emphasis will be put on controlling and quantifying systematic errors. This work is performed as part of a Budapest-Marseille-Wuppertal + Regensburg collaboration.

172. Flavour Symmetry and Flavour Symmetry Breaking in 2+1 Flavour lattice simulations

Paul Rakow (University of Liverpool)

15/06/2010, 15:30

Hadron spectroscopy

The QCD interaction is flavour-blind. Neglecting electromagnetic and weak interactions, the only difference between flavours comes from the mass matrix. We investigate how flavour-blindness constrains hadron masses after flavour SU(3) is broken by the mass difference between the strange and light quarks, to help us extrapolate 2+1 flavour lattice data to the physical point. We have...

182. Tuning the strange quark mass and the hadron mass spectrum for 2+1 quark flavours

Roger Horsley (University of Edinburgh)

15/06/2010, 15:50

Hadron spectroscopy

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 ...