2001/08/31 by N. Brambilla, Y. Sumino, A. Vairo · 1 citation
Physics and Astronomy · #hep-ph
paper · pdf · doi:10.1103/physrevd.65.034001
published as Phys.Rev.D65:034001,2002 · 33 pages, 21 figures; v2: Abstract modified; Table7 (summary of errors) added; Version to appear in Phys.Rev.D
arxiv created 2001/10/04 · arxiv updated 2009/11/30
We study the spectra of the bottomonium and Bc states within perturbative QCD up to order alphas4. The O(LambdaQCD) renormalon cancellation between the static potential and the pole mass is performed in the epsilon-expansion scheme. We extend our previous analysis by including the (dominant) effects of non-zero charm-quark mass in loops up to the next-to-leading non-vanishing order epsilon3. We fix the b-quark MSbar mass mb ≡ mb^\rm MS(mb^\rm MS) on Upsilon(1S) and compute the higher levels. The effect of the charm mass decreases mb by about 11 MeV and increases the n=2 and n=3 levels by about 70--100 MeV and 240--280 MeV, respectively. We provide an extensive quantitative analysis. The size of non-perturbative and higher order contributions is discussed by comparing the obtained predictions with the experimental data. An agreement of the perturbative predictions and the experimental data depends crucially on the precise value (inside the present error) of alphas(MZ). We obtain mb^\rm MS(mb^\rm MS) = 4190 ± 20 ± 25 ± 3 ~ \rm MeV.