Physics – High Energy Physics – High Energy Physics - Lattice
Scientific paper
2008-03-21
Phys.Rev.D78:014509,2008
Physics
High Energy Physics
High Energy Physics - Lattice
19 pages, 18 figures, Version as accepted in Phys. Rev. D, Discussion on nucleon sigma-term extended, typos corrected
Scientific paper
10.1103/PhysRevD.78.014509
We present results on the mass of the nucleon and the Delta using two dynamical degenerate twisted mass quarks and the tree-level Symanzik improved gauge action. The evaluation is performed at four quark masses corresponding to a pion mass in the range of about 300-600 MeV on lattices of 2.1-2.7 fm. We check for cut-off effects by evaluating these baryon masses on lattices of spatial size 2.1 fm at beta=3.9 and beta=4.05 and on a lattice of 2.4 fm at beta=3.8. The values we find are compatible within our statistical errors. Lattice results are extrapolated to the physical limit using continuum chiral perturbation theory. Performing a combined fit to our lattice data at beta=3.9 and beta=4.05 we find a nucleon mass of 964\pm 28 (stat.) \pm 8 (syst.) MeV. The nucleon mass at the physical point provides an independent determination of the lattice spacing. Using heavy baryon chiral perturbation theory at O(p^3) we find a_{\beta=3.9}=0.0890\pm 0.0039(stat.) \pm 0.0014(syst.) fm, and a_{\beta=4.05}= 0.0691\pm 0.0034(stat.) \pm 0.0010(syst.) fm, in good agreement with the values determined from the pion decay constant. Isospin violating lattice artifacts in the Delta-system are found to be compatible with zero for the values of the lattice spacings used in this work. Performing a combined fit to our lattice data at beta=3.9 and beta=4.05 we find for the masses of the Delta^{++,-} and Delta^{+,0} 1316 \pm 60 (stat.) MeV and 1330 \pm 74 (stat.) MeV respectively. We confirm that in the continuum limit they are also degenerate.
Alexandrou Constantia
Baron Remi
Blossier Benoit
Brinet Mariane
Carbonell Jaime
No associations
LandOfFree
Light baryon masses with dynamical twisted mass fermions does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Light baryon masses with dynamical twisted mass fermions, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Light baryon masses with dynamical twisted mass fermions will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-587462