Decay Constants of Beauty Mesons from QCD Sum Rules
1 Institute for High Energy Physics, Austrian Academy of Sciences, Nikolsdorfergasse 18, A-1050 Vienna, Austria
2 Faculty of Physics, University of Vienna, Boltzmanngasse 5, A-1090 Vienna, Austria
3 D. V. Skobeltsyn Institute of Nuclear Physics, M. V. Lomonosov Moscow State University, 119991, Moscow, Russia
4 INFN, Sezione di Roma Tre, Via della Vasca Navale 84, I-00146, Roma, Italy
a e-mail: Wolfgang.Lucha@oeaw.ac.at
b e-mail: firstname.lastname@example.org
c e-mail: email@example.com
Published online: 24 November 2014
Our recently completed analysis of the decay constants of both pseudoscalar and vector beauty mesons reveals that in the bottom-quark sector two specific features of the sum-rule predictions show up: (i) For the input value of the bottom-quark mass in the M̅S̅ scheme m̅b(m̅b) ≈ 4:18 GeV; the sum-rule result fB ≈ 210–220 MeV for the B meson decay constant is substantially larger than the recent lattice-QCD finding fB ≈ 190 MeV: Requiring QCD sum rules to reproduce the lattice-QCD value of fB yields a significantly larger b-quark mass: m̅b(m̅b) = 4:247 GeV: (ii) Whereas QCD sum-rule predictions for the charmed-meson decay constants fD; fDs, fD* and fDs* are practically independent of the choice of renormalization scale, in the beauty sector the results for the decay constants—and especially for the ratio fB* / fB—prove to be very sensitive to the specific scale setting.
© Owned by the authors, published by EDP Sciences, 2014
This is an Open Access article distributed under the terms of the Creative Commons Attribution License 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.