Non-perturbatively renormalized light-quark masses with the alpha action

Citation
D. Becirevic et al., Non-perturbatively renormalized light-quark masses with the alpha action, PHYS LETT B, 444(3-4), 1998, pp. 401-410
Citations number
37
Categorie Soggetti
Physics
Journal title
PHYSICS LETTERS B
ISSN journal
03702693 → ACNP
Volume
444
Issue
3-4
Year of publication
1998
Pages
401 - 410
Database
ISI
SICI code
0370-2693(199812)444:3-4<401:NRLMWT>2.0.ZU;2-L
Abstract
We have computed the light quark masses using the O(a(2)) improved Alpha ac tion, in the quenched approximation. The renormalized masses have been obta ined non-perturbatively. By eliminating the systematic error coming from th e truncation of the perturbative series, our procedure removes the discrepa ncies, observed in previous calculations, between the results obtained usin g the vector and the axial-vector Ward identities. It also gives values of the quark masses larger than those obtained by computing the renormalizatio n constants using (boosted) perturbation theory. Our main results, in the R I (MOM) scheme and at a renormalization scale mu = 2 GeV, are m(s)(RI) = 13 8(15) MeV and m(i)(RI) = 5.6(5) MeV, where m(s)(RI) is the mass of the stra nge quark and m(l)(RI) = (m(u)(RI) + m(d)(RI))/2 the average mass of the up -down quarks. From these results, which have been obtained non-perturbative ly, by using continuum perturbation theory we derive the MS masses, at the same scale, and the renormalization group invariant (m(RGI)) masses. We fin d m(s)(NLO MS) = 121(13) MeV and m(l)(NLO MS) = 4.9(4) MeV at the next-to-l eading order; m(s)(N2 LO MS) = 111(12) MeV, m(l)(N2) (LO) (MS) = 4.5(4) MeV , m(s)(RGI) = 177(19) MeV and m(l)(RGI) = 7.2(6) MeV at the next-to-next-to -leading order. (C) 1998 Published by Elsevier Science B.V. All rights rese rved.