Sizing the double pole resonant enhancement in $e^{+}e^{-} \to π^{0} π^{0} γ$ cross section and $τ^{-} \to π^{-}π^{0} ν_τγ$ decay

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Esparza-Arellano, Leonardo, Rojas, Antonio, Toledo, Genaro
Format: Preprint
Published: 2023
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866914690914844672
author Esparza-Arellano, Leonardo
Rojas, Antonio
Toledo, Genaro
author_facet Esparza-Arellano, Leonardo
Rojas, Antonio
Toledo, Genaro
contents The enhancement mechanism due to the resonant properties of the $ρ$ and $ω$ mesons, which are close in mass, are analysed when such resonances carry different momenta. Considerations from the particular process where they appear to the individual resonant features are at play for the appearance of the global resonant manifestation. In this work, we first consider the $e^+e^- \to π^0 π^0 γ$ process. We use the differential cross section at a given angle of emission of one of the pions, to tune the individual features of the two resonances and exhibit how both resonances combine to produce the enhancement. Then, we incorporate the $ρ^\prime$ using the information obtained from the $ e^+e^- \to π^0 π^0 γ$ total scattering process and show that, it becomes important thanks to the same enhancement mechanism between the $ρ$ and the $ω$. In a second step, we use a similar approach to describe a model dependent contribution to the $τ^- \to π^-π^0ν_τγ$ decay, the so-called $ω$ channel. We show that the dipion invariant mass distribution at particular angles is sensitive to the individual resonant states. We compute the interference of this channel with the known dominant model independent contribution, and show how a better knowledge of the $e^+e^- \to π^0 π^0 γ$ process can help to properly account for such model dependent effects. The implication on the isospin symmetry breaking correction to tau-based estimates of the muon magnetic dipole moment is assessed.
format Preprint
id arxiv_https___arxiv_org_abs_2308_02766
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle Sizing the double pole resonant enhancement in $e^{+}e^{-} \to π^{0} π^{0} γ$ cross section and $τ^{-} \to π^{-}π^{0} ν_τγ$ decay
Esparza-Arellano, Leonardo
Rojas, Antonio
Toledo, Genaro
High Energy Physics - Phenomenology
The enhancement mechanism due to the resonant properties of the $ρ$ and $ω$ mesons, which are close in mass, are analysed when such resonances carry different momenta. Considerations from the particular process where they appear to the individual resonant features are at play for the appearance of the global resonant manifestation. In this work, we first consider the $e^+e^- \to π^0 π^0 γ$ process. We use the differential cross section at a given angle of emission of one of the pions, to tune the individual features of the two resonances and exhibit how both resonances combine to produce the enhancement. Then, we incorporate the $ρ^\prime$ using the information obtained from the $ e^+e^- \to π^0 π^0 γ$ total scattering process and show that, it becomes important thanks to the same enhancement mechanism between the $ρ$ and the $ω$. In a second step, we use a similar approach to describe a model dependent contribution to the $τ^- \to π^-π^0ν_τγ$ decay, the so-called $ω$ channel. We show that the dipion invariant mass distribution at particular angles is sensitive to the individual resonant states. We compute the interference of this channel with the known dominant model independent contribution, and show how a better knowledge of the $e^+e^- \to π^0 π^0 γ$ process can help to properly account for such model dependent effects. The implication on the isospin symmetry breaking correction to tau-based estimates of the muon magnetic dipole moment is assessed.
title Sizing the double pole resonant enhancement in $e^{+}e^{-} \to π^{0} π^{0} γ$ cross section and $τ^{-} \to π^{-}π^{0} ν_τγ$ decay
topic High Energy Physics - Phenomenology
url https://arxiv.org/abs/2308.02766