Ref Arxiv: 1105.5070
Ref. & Cit.: NASA ADS
Résumé:

We test the convergence of the QCD exponential moments by including PT corrections to order \alpha_s^3 and the NP contributions up to D=8 condensates. Then, using the ratio of exponential sum rules where the QCD PT series is more convergent, we study the correlation between the gluon condensates <\alpha_s G^2> and < g^3f_{abc} G^3>. From charmonium systems and using the charm quark mass as input, we deduce:< g^3f_{abc} G^3> =(8.2+-1.0)GeV^2 <\alpha_s G^2> corresponding to < \alpha_s G^2>=(7.5+- 2.0) 10^{-2} GeV^4. Using these results for the bottomium systems, we obtain: m_b(m_b)= 4212(32) MeV, which is slightly higher but consistent within the errrors with the ones from Q^2-moments and their ratios: m_b(m_b)= 4172(12) MeV. We are tempted to consider as a final result from the sum rules approaches, the average m_b(m_b)= 4177(11) MeV of the two previous determinations.

Commentaires: 5 pages, 4 figures, 2 references added on the proofs (Phys. Lett. B in press)