0000000000331127
AUTHOR
Rainer Sommer
showing 4 related works from this author
A one-loop study of matching conditions for static-light flavor currents
2012
Heavy Quark Effective Theory (HQET) computations of semi-leptonic decays, e.g. B -> pi l nu, require the knowledge of the parameters in the effective theory for all components of the heavy-light flavor currents. So far non-perturbative matching conditions have been employed only for the time component of the axial current. Here we perform a check of matching conditions for the time component of the vector current and the spatial component of the axial vector current up to one-loop order of perturbation theory and to lowest order of the 1/m-expansion. We find that the proposed observables have small higher order terms in the 1/m-series and are thus excellent candidates for a non-perturbat…
Decay constants of B-mesons from non-perturbative HQET with two light dynamical quarks
2014
We present a computation of B-meson decay constants from lattice QCD simulations within the framework of Heavy Quark Effective Theory for the b-quark. The next-to-leading order corrections in the HQET expansion are included non-perturbatively. Based on Nf=2 gauge field ensembles, covering three lattice spacings a (0.08-0.05)fm and pion masses down to 190MeV, a variational method for extracting hadronic matrix elements is used to keep systematic errors under control. In addition we perform a careful autocorrelation analysis in the extrapolation to the continuum and to the physical pion mass limits. Our final results read fB=186(13)MeV, fBs=224(14)MeV and fBs/fB=1.203(65). A comparison with o…
The b-quark mass from non-perturbative Nf=2 Heavy Quark Effective Theory at O(1/mh)
2014
Abstract We report our final estimate of the b-quark mass from N f = 2 lattice QCD simulations using Heavy Quark Effective Theory non-perturbatively matched to QCD at O ( 1 / m h ) . Treating systematic and statistical errors in a conservative manner, we obtain m ¯ b MS ¯ ( 2 GeV ) = 4.88 ( 15 ) GeV after an extrapolation to the physical point.
Heavy-strange meson decay constants in the continuum limit of quenched QCD
2007
We improve a previous quenched result for heavy-light pseudoscalar meson decay constants with the light quark taken to be the strange quark. A finer lattice resolution (a ~ 0.05 fm) in the continuum limit extrapolation of the data computed in the static approximation is included. We also give further details concerning the techniques used in order to keep the statistical and systematic errors at large lattice sizes L/a under control. Our final result, obtained by combining these data with determinations of the decay constant for pseudoscalar mesons around the D_s, follows nicely the qualitative expectation of the 1/m-expansion with a (relative) 1/m-term of about -0.5 GeV/m_PS. At the physic…