The τ → ντπe+e − decay revisited


  • Adolfo Guevara IFIC



Resonance chiral theory, chiral lagrangians, hadronic tau decays, Belle physics


The recent results from Belle of the τ − → ντπ −e +e − analysis have incentivated us to make a reanalysis of a former work where the Structure Dependent parts are obtained using Resonance Chiral Theory. Here we rely on the same theory accounting for effects that explicitly break such symmetry. A motivation is the involved W πγ? vertex, utterly relevant in computing τ − → ντπ − radiative corrections.


A. Guevara, G. Lopez Castro and P. Roig, Improved de- ´ scription of di-lepton production in τ − → ντP − decays, [arXiv:2111.09994 [hep-ph]].

K. Kampf, J. Novotny and P. Sanchez-Puertas, Radia- ´ tive corrections to double-Dalitz decays revisited, Phys. Rev. D 97 (2018) 056010,

T. Husek, K. Kampf, S. Leupold and J. Novotny, Radiative corrections to the η (0) Dalitz decays, Phys. Rev. D 97 (2018) 096013,

A. Guevara, G. Lopez-Castro and P. Roig, τ − → η (0)π −ντ γ decays as backgrounds in the search for second class currents, Phys. Rev. D 95 (2017) 054015,

A. Guevara, G. Lopez Castro, P. Roig and S. L. Tostado, Long-distance weak annihilation contribution to the B ± → (π ±, K±)ell +ell − decays, Phys. Rev. D 92 (2015) 054035,

Z. H. Guo and P. Roig, One meson radiative tau decays, Phys. Rev. D 82 (2010) 113016,

Y. Jin et al. [Belle], Observation of τ − → π −ντ e +e − and search for τ − → π −ντµ +µ −, Phys. Rev. D 100 (2019) 071101,

A. Guevara, G. Lopez Castro and P. Roig, Weak radiative pion ´ vertex in τ − → π −ντ ` +` − decays, Phys. Rev. D 88 (2013) 033007, 033007.

G. Ecker, J. Gasser, A. Pich and E. de Rafael, The Role of Resonances in Chiral Perturbation Theory, Nucl. Phys. B 321 (1989) 311,

G. Ecker, J. Gasser, H. Leutwyler, A. Pich and E. de Rafael, Chiral Lagrangians for Massive Spin 1 Fields, Phys. Lett. B 223 (1989) 425,

S. Weinberg, Phenomenological Lagrangians, Physica A 96 (1979) 327, 0378-4371(79)90223-1.

J. Gasser and H. Leutwyler, Chiral Perturbation Theory to One Loop, Annals Phys. 158 (1984) 142,

J. Gasser and H. Leutwyler, Chiral Perturbation Theory: Expansions in the Mass of the Strange Quark, Nucl. Phys. B 250 (1985) 465,

V. Cirigliano, G. Ecker, M. Eidemuller, A. Pich and J. Portoles, The < VAP > Green function in the resonance region, 596 (2004) 96,

V. Cirigliano, G. Ecker, M. Eidemüller, R. Kaiser, A. Pich and J. Portoles, Towards a consistent estimate of the chiral low-energy constants, Nucl. Phys. B 753 (2006) 139, https: //

P. D. Ruiz-FemenAa, A. Pich and J. Portoles, Odd intrinsic parity processes within the resonance effective theory of QCD, JHEP 07 (2003) 003,

K. Kampf and J. Novotny, Resonance saturation in the odd-intrinsic parity sector of low-energy QCD, Phys. Rev. D 84 (2011) 014036,

A. Guevara, P. Roig and J. J. Sanz-Cillero, Pseudoscalar pole light-by-light contributions to the muon (g − 2) in Resonance Chiral Theory, JHEP 06 (2018) 160,

M. Knecht and A. Nyffeler, Resonance estimates of O(p**6) low-energy constants and QCD short distance constraints, Eur. Phys. J. C 21 (2001) 659,

G. P. Lepage and S. J. Brodsky, Exclusive Processes in Perturbative Quantum Chromodynamics, Phys. Rev. D 22 (1980) 2157.

S. J. Brodsky and G. R. Farrar, Scaling Laws at Large Transverse Momentum, Phys. Rev. Lett. 31 (1973), 1153-1156.

P. Roig and J. J. Sanz Cillero, Consistent high-energy constraints in the anomalous QCD sector, Phys. Lett. B 733 (2014) 158,

J. A. Miranda and P. Roig, New τ -based evaluation of the hadronic contribution to the vacuum polarization piece of the muon anomalous magnetic moment, Phys. Rev. D 102 (2020) 114017.




How to Cite

Guevara A. The τ → ντπe+e − decay revisited. Supl. Rev. Mex. Fis. [Internet]. 2022 May 19 [cited 2022 Dec. 7];3(3):0308052 1-6. Available from: