Strong coupling from e(+)e(-) -> hadrons below charm

Autor(es)

Boito, Diogo ^[1] ; Golterman, Maarten ^{[2, 3, 4]} ; Keshavarzi, Alexander ^{[5, 6]} ; Maltman, Kim ^{[7, 8]} ; Nomura, Daisuke ^[9] ; Peris, Santiago ^{[2, 4]} ; Teubner, Thomas ^[6]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Fis Sao Carlos, CP 369, BR-13570970 Sao Carlos, SP - Brazil

^[2] Univ Autonoma Barcelona, Dept Phys, E-08193 Barcelona - Spain

^[3] San Francisco State Univ, Dept Phys & Astron, San Francisco, CA 94132 - USA

^[4] Univ Autonoma Barcelona, IFAE BIST, E-08193 Barcelona - Spain

^[5] Univ Mississippi, University, MS 38677 - USA

^[6] Univ Liverpool, Dept Math Sci, Liverpool L69 3BX, Merseyside - England

^[7] Univ Adelaide, CSSM, Adelaide, SA 5005 - Australia

^[8] York Univ, Dept Math & Stat, Toronto, ON M3J 1P3 - Canada

^[9] KEK Theory Ctr, Tsukuba, Ibaraki 3050801 - Japan

• Tipo de documento: Artigo Científico
• Fonte: Physical Review D; v. 98, n. 7 OCT 31 2018.
• Citações Web of Science: 2

Resumo

We use a new compilation of the hadronic R-ratio from available data for the process e(+)e(-) -> hadrons to determine the strong coupling, as. We make use of all data for the R-ratio from threshold to a center-of-mass energy of 2 GeV by employing finite-energy sum rules. Data above 2 GeV, for which at present far fewer high-precision experimental data are available, do not provide much additional constraint but are fully consistent with the values for as we obtain. Quoting our results at the t mass to facilitate comparison to the results obtained from analogous analyses of hadronic tau-decay data, we find alpha(s)(m(tau)(2)) = 0.298 +/- 0.016 +/- 0.006 in fixed-order perturbation theory, and alpha(s)(m(tau)(2)) = 0.304 +/- 0.018 +/- 0.006 in contour-improved perturbation theory, where the first error is statistical, and the second error reflects our estimate of various systematic effects. These values are in good agreement with a recent determination from the OPAL and ALEPH data for hadronic tau decays. (AU)

• Processo FAPESP: 15/20689-9 - Determinação precisa de parâmetros fundamentais da QCD
• Beneficiário: Diogo Rodrigues Boito
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores