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ID 14577
本文ファイル
著者
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
物理学
抄録(英)
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.
掲載誌名
Physical Review D
70巻
開始ページ
074503
出版年月日
2004
出版者
The American Physical Society
ISSN
1550-7998
言語
英語
NII資源タイプ
学術雑誌論文
広大資料タイプ
学術雑誌論文
DCMIタイプ
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フォーマット
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著者版フラグ
publisher
権利情報
Copyright (c) 2004 The American Physical Society
関連情報URL(IsVersionOf)
http://dx.doi.org/10.1103/PhysRevD.70.074503
部局名
理学研究科