English

Borel-Laplace Sum Rules with $\tau$ decay data, using OPE with improved anomalous dimensions

High Energy Physics - Phenomenology 2023-03-20 v3

Abstract

We perform numerical analysis of double-pinched Borel-Laplace QCD sum rules for the strangeless semihadronic τ\tau-decay data. The D=0D=0 contribution to the theoretical contour integral in the sum rules is evaluated by the (truncated) Fixed Order perturbation theory method (FO) and by the Principal Value (PV) of the Borel integration. We use for the full Adler function the Operator Product Expansion (OPE) with the terms OD\sim \langle O_D \rangle of dimension D=2nD=2 n where 2n52 \leq n \leq 5 for the (V+A)-channel, and 2n72 \leq n \leq 7 for the V-channel data. In our previous works [1,2], only the (V+A)-channel data was analysed. In this work, the analysis of a new set of V-channel data is performed as well. Further, a renormalon-motivated construction of the D=0D=0 part of the Adler function is improved in the u=3u=3 infrared renormalon sector, by involving the recently known information on the two principal noninteger values k(j)=γ(1)(O6(j))/β0k^{(j)}=\gamma^{(1)}(O_6^{(j)})/\beta_0 of the effective leading-order anomalous dimensions. Additionally, the OPE of the Adler function has now the D=6 contribution with the principal anomalous dimension (αsk(1)\sim \alpha_s^{k^{(1)}}), and terms of higher dimension (with zero anomalous dimension). Cross-checks of the obtained extracted values of αs\alpha_s and of the condensates were performed by reproduction of the (central) experimental values of several double-pinched momenta a(2,n)a^{(2,n)}. The averaged final extracted values of the (MSbar) coupling are: αs(mτ2)=0.31690.0096+0.0070\alpha_s(m_{\tau}^2) = 0.3169^{+0.0070}_{-0.0096}, corresponding to αs(MZ2)=0.11830.0012+0.0009\alpha_s(M_Z^2)=0.1183^{+0.0009}_{-0.0012}.

Keywords

Cite

@article{arxiv.2206.05631,
  title  = {Borel-Laplace Sum Rules with $\tau$ decay data, using OPE with improved anomalous dimensions},
  author = {Cesar Ayala and Gorazd Cvetic and Diego Teca},
  journal= {arXiv preprint arXiv:2206.05631},
  year   = {2023}
}

Comments

29 pages, 10 figures; v3: minor changes in the text, version as published in J.Phys.G

R2 v1 2026-06-24T11:47:44.889Z