@Article{Guevara_etal2022,
author="Guevara, A.
and Lopez Castro, G.
and Roig, P.",
title="Improved description of dilepton production in tau(-) -> nu(tau)P(- )decays",
journal="Physical Review D",
year="2022",
publisher="Amer Physical Soc",
volume="105",
number="7",
pages="076007--15pp",
abstract="Recently, the Belle Collaboration reported the first measurements of the tau(-) -> nu(tau)pi(-) e(+) e(-) branching fraction and the spectrum of the pion-dielectron system. In an analysis previous to Belle{\textquoteright}s results, we evaluated this branching fraction which turned out to be compatible with that reported by Belle, although with a large uncertainty. This is the motivation to seek for improvement on our previous evaluation of tau(-) -> nu(tau)pi(-) l(+) l(-) decays (l = e, mu). In this paper we improve our calculation of the WP-gamma* vertex by including flavor-symmetry breaking effects in the framework of the resonance chiral theory. We impose QCD short-distance behavior to constrain most parameters and data on the pi(-) e(+) e(-) spectrum reported by the Belle Collaboration to fix the remaining free ones. As a result, improved predictions for the branching ratios and hadronic/leptonic spectra are reported, which are in good agreement with observations. Analogous calculations for the strangeness-changing tau(-) -> nu(tau) K- l(+) l(-) transitions are reported for the first time. Albeit one expects the m(pi mu+ mu- )spectrum to be measured in Belle-II and the observables with l = e can be improved, it is rather unlikely that the K channels can be measured due to the suppression factor vertical bar V-ud/V-us vertical bar(2) = 0.05.",
optnote="WOS:000789304200003",
optnote="exported from refbase (https://references.ific.uv.es/refbase/show.php?record=5212), last updated on Thu, 12 May 2022 10:22:42 +0000",
issn="2470-0010",
doi="10.1103/PhysRevD.105.076007",
opturl="https://arxiv.org/abs/2111.09994",
opturl="https://doi.org/10.1103/PhysRevD.105.076007",
language="English"
}