Generalized structure functions are derived for tau decays including tensor beyond-SM contributions, enabling maximal model-independent use of data for CP/T violation studies.
tau -> pi pi pi nu_tau decays and the a_1(1260) off-shell width revisited
2 Pith papers cite this work. Polarity classification is still indexing.
abstract
The tau -> pi pi pi nu_tau decay is driven by the hadronization of the axial-vector current. Within the resonance chiral theory, and considering the large-Nc expansion, this process has been studied in Ref.[1]. In the light of later developments we revise here this previous work by including a new off-shell width for the lightest a_1 resonance that provides a good description of the tau -> pi pi pi nu_tau spectrum and branching ratio. We also consider the role of the rho(1450) resonance in these observables. Thus we bring in an overall description of the tau -> pi pi pi nu_tau process in excellent agreement with our present experimental knowledge.
fields
hep-ph 2years
2025 2representative citing papers
Chiral effective field theory and resonance chiral theory yield cross sections for e+e- to four pions that are one to two orders smaller than data, with hadronic vacuum polarization contributions to (g-2)μ of (0.680±0.062)×10^{-16} and (0.597±0.058)×10^{-16} for the two charge modes.
citing papers explorer
-
Generalized structure functions in semileptonic tau decays
Generalized structure functions are derived for tau decays including tensor beyond-SM contributions, enabling maximal model-independent use of data for CP/T violation studies.
-
Study of electron-positron annihilation into four pions within chiral effective field theory in the low energy region
Chiral effective field theory and resonance chiral theory yield cross sections for e+e- to four pions that are one to two orders smaller than data, with hadronic vacuum polarization contributions to (g-2)μ of (0.680±0.062)×10^{-16} and (0.597±0.058)×10^{-16} for the two charge modes.