English

A fresh look into the heavy quark-mass values

High Energy Physics - Phenomenology 2011-01-27 v1 High Energy Physics - Lattice

Abstract

Using the recent {\it world average} αs(MZ2)=0.118±0.006\alpha_s(M^2_Z)= 0.118 \pm 0.006, we give the {\it first direct extraction} from the Ψ\Psi and Υ\Upsilon data of the values of the {\it running heavy quark masses} within QCD spectral sum rules to two-loops in the MS\overline {MS}-scheme: \mrb(MbPT2)\mr_b(M^{PT2}_b) = (4.23 0.04+0.03±0.02)(4.23~^{+0.03}_{-0.04} \pm 0.02) GeV and \mrc(McPT2)\mr_c(M^{PT2}_c) = (1.23 0.04+0.02±0.03)(1.23~^{+ 0.02}_{-0.04} \pm 0.03) GeV, (the errors are respectively due to \alf\alf and to the gluon condensate), and the corresponding value of the {\it short-distance perturbative pole masses to two-loops}: MbPT2=(4.62±0.02)M^{PT2}_b=(4.62 \pm 0.02) GeV, McPT2=(1.41±0.03)M^{PT2}_c= (1.41\pm 0.03) GeV, which we compare with the updated values of the {\it non-relativistic pole masses} re-extracted {\it directly} from the two-loop non-relativistic sum rules: MbNR=(4.69 +0.020.01±0.02)M^{NR}_b= (4.69~^{-0.01}_{+0.02} \pm 0.02) GeV and McNR=(1.44±0.02±0.03)M^{NR}_c=(1.44\pm 0.02\pm 0.03) GeV. It is also informative to compare the {\it three-loop} values of the short-distance pole masses: MbPT3=(4.87±0.05±0.02)M^{PT3}_b=(4.87\pm 0.05 \pm 0.02) GeV and McPT3=(1.62±0.07±0.03)M^{PT3}_c= (1.62\pm 0.07 \pm 0.03) GeV, with the {\it dressed mass} Mbnr=(4.94±0.10±0.03)M^{nr}_b = (4.94 \pm 0.10 \pm 0.03) GeV, entering into the {\it non-relativistic Balmer formula} including higher order \alf\alf corrections. The smallsmall mass-differences MbNRMbPT2MbnrMbPT370M^{NR}_b-M^{PT2}_b \simeq M^{nr}_b-M^{PT3}_b \simeq 70 MeV and McNRMcPT2(30±20)M_c^{NR}-M_c^{PT2} \simeq (30 \pm 20) MeV {\it can measure the size} of the non-perturbative effect induced by {\it renormalon} type-singularities. An analogous analysis is pursued for the heavy-light mesons, where a simultaneous {\it re-fit} of the BB and BB^* masses from relativistic sum rules leads to: MbPT2=(4.63±0.08)M_b^{PT2}= (4.63 \pm 0.08) GeV,

Keywords

Cite

@article{arxiv.hep-ph/9408376,
  title  = {A fresh look into the heavy quark-mass values},
  author = {S. Narison},
  journal= {arXiv preprint arXiv:hep-ph/9408376},
  year   = {2011}
}

Comments

15 pages in latex file + 3 figures in 3 ps-files appended at the end of the paper, CERN-TH.7405/94 (replace 9408376 : compressed abstract)