We compute the mass of the b-quark and the Bs meson decay constant in quenched lattice QCD using a combination of HQET and the standard relativistic QCD Lagrangian. We start from a small volume, where one can directly deal with the b-quark, and compute the evolution to a big volume, where the finite size effects are negligible through step scaling functions which give the change of the observables when L is changed to 2L. In all steps we extrapolate to the continuum limit, separately in HQET and in QCD for masses below mb. The point mb is then reached by an interpolation of the continuum results. With r0 = 0.5fm and the experimental Bs and K masses we find fBs = 191(6) MeV and the renormalization group invariant mass Mb = 6.89(11) GeV, translating into mb(mb) = 4.42(7) GeV in the MS scheme.
Guazzini, D., Sommer, R., Tantalo, N. (2006). Mb and fBs from a combination of HQET and QCD. POS PROCEEDINGS OF SCIENCE, 32.
Mb and fBs from a combination of HQET and QCD
Tantalo, N
2006-01-01
Abstract
We compute the mass of the b-quark and the Bs meson decay constant in quenched lattice QCD using a combination of HQET and the standard relativistic QCD Lagrangian. We start from a small volume, where one can directly deal with the b-quark, and compute the evolution to a big volume, where the finite size effects are negligible through step scaling functions which give the change of the observables when L is changed to 2L. In all steps we extrapolate to the continuum limit, separately in HQET and in QCD for masses below mb. The point mb is then reached by an interpolation of the continuum results. With r0 = 0.5fm and the experimental Bs and K masses we find fBs = 191(6) MeV and the renormalization group invariant mass Mb = 6.89(11) GeV, translating into mb(mb) = 4.42(7) GeV in the MS scheme.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.