English

Higher twists and $\alpha_s(M_Z)$ extractions from the NNLO QCD analysis of the CCFR data for $xF_3$ structure function

High Energy Physics - Phenomenology 2009-10-31 v3

Abstract

A detailed next-to-next-to-leading order (NNLO) QCD analysis is performed for the experimental data of the CCFR collaboration for the xF3xF_3 structure function. Theoretical ambiguities of the results of our NNLO fits are estimated by application of the Pad\'e resummation technique and variation of the factorization and renormalization scales. The NNLO and N3^3LO αs(Q2)\alpha_s(Q^2) MSˉ\bar{MS}-matching conditions are used. In the process of the fits we are taking into account of twist-4 1/Q21/Q^2-terms. We found that the amplitude of the xx-shape of the twist-4 factor is decreasing in NLO and NNLO, though some remaining twist-4 structure seems to retain in NNLO in the case when statistical uncertainties are taken into account. The question of the stability of these results to the application of the [0/2] Pad\'e resummation technique is considered. Our NNLO results for αs(MZ)\alpha_s(M_Z) values, extracted from the CCFR xF3xF_3 data, are αs(MZ)=0.118±0.002(stat)±0.005(syst)±0.003(theory)\alpha_s(M_Z)=0.118 \pm 0.002 (stat) \pm 0.005 (syst)\pm 0.003 (theory) provided the twist-4 contributions are fixed through the infrared renormalon model and αs(MZ)=0.1210.010+0.007(stat)±0.005(syst)±0.003(theory)\alpha_s(M_Z)=0.121^{+0.007}_{0.010}(stat)\pm 0.005 (syst) \pm 0.003 (theory) provided the twist-4 terms are considered as free parameters.

Keywords

Cite

@article{arxiv.hep-ph/9905310,
  title  = {Higher twists and $\alpha_s(M_Z)$ extractions from the NNLO QCD analysis of the CCFR data for $xF_3$ structure function},
  author = {A. L. Kataev and G. Parente and A. V. Sidorov},
  journal= {arXiv preprint arXiv:hep-ph/9905310},
  year   = {2009}
}

Comments

33 pages LaTeX, 3 ps figures; minor misprints are eliminated, 2 new referencies are added; accepted for publication in Nucl. Phys. B