Nonperturbative O(a) improvement of the Wilson quark action with the renormalization-group-improved gauge action using the Schrödinger functional method

CP-PACS Collaboration

JLQCD Collaboration

Aoki S

Fukugita M

Hashimoto S

Ishikawa Kenichi

Ishizuka N

Iwasaki Y

Kanaya K

Kaneko T

Kuramashi Y

Okawa Masanori

Takeda S

Taniguchi Y

Tsutsui N

Ukawa A

Yamada N

Yoshié T

Physical Review D

We perform a nonperturbative determination of the O(a)-improvement coefficient cSW and the critical hopping parameter kappac for Nf=3, 2, and 0 flavor QCD with the (RG) renormalization-group-improved gauge action using the Schrödinger functional method. In order to interpolate cSW and kappac as a function of the bare coupling, a wide range of beta from the weak coupling region to the moderately strong coupling points used in large-scale simulations is studied. Corrections at finite lattice size of O(a/L) turned out to be large for the RG-improved gauge action, and hence we make the determination at a size fixed in physical units using a modified improvement condition. This enables us to avoid O(a) scaling violations which would remain in physical observables if cSW determined for a fixed lattice size L/a is used in numerical simulations.

Physics [ 420 ]

eng

The American Physical Society

Copyright (c) 2006 The American Physical Society

[ISSN] 1550-7998

[DOI] http://dx.doi.org/10.1103/PhysRevD.73.014511 isVersionOf