このエントリーをはてなブックマークに追加
ID 14577
file
creator
CP-PACS, Collaboration
Namekawa, Y
Aoki, S
Fukugita, M
Ishizuka, N
Iwasaki, Y
Kanaya, K
Kaneko, T
Kuramashi, Y
Lesk, V. I.
Ukawa, A
Umeda, T
Yoshié, T
NDC
Physics
abstract
We extend the study of the light hadron spectrum and the quark mass in two-flavor QCD to smaller sea quark mass, corresponding to mPS/mV=0.60–0.35. Numerical simulations are carried out using the RG-improved gauge action and the meanfield-improved clover quark action at beta=1.8 (a=0.2 fm from rho meson mass). We observe that the light hadron spectrum for small sea quark mass does not follow the expectation from chiral extrapolations with quadratic functions made from the region of mPS/mV=0.80–0.55. Whereas fits with either polynomial or continuum chiral perturbation theory (ChPT) fail, the Wilson ChPT (WChPT) that includes a2 effects associated with explicit chiral symmetry breaking successfully fits the whole data: In particular, WChPT correctly predicts the light quark mass spectrum from simulations for medium heavy quark mass, such as mPS/mV>~0.5. Reanalyzing the previous data with the use of WChPT, we find the mean up and down quark mass being smaller than the previous result from quadratic chiral extrapolation by approximately 10%, mudMS-bar(µ=2 GeV)=3.11(17) [MeV] in the continuum limit.
journal title
Physical Review D
volume
Volume 70
start page
074503
date of issued
2004
publisher
The American Physical Society
issn
1550-7998
language
eng
nii type
Journal Article
HU type
Journal Articles
DCMI type
text
format
application/pdf
text version
publisher
rights
Copyright (c) 2004 The American Physical Society
relation is version of URL
http://dx.doi.org/10.1103/PhysRevD.70.074503
department
Graduate School of Science



Last 12 months's access : ? times
Last 12 months's DL: ? times


This month's access: ? times
This month's DL: ? times