Saved in:
| Main Authors: | , , |
|---|---|
| Format: | Preprint |
| Published: |
2026
|
| Subjects: | |
| Online Access: | https://arxiv.org/abs/2604.25673 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
Table of Contents:
- In this work we explore the semileptonic $τ$ decays into the axion-like particle ($a$)-meson final states within chiral effective field theory. The next-to-leading-order mixing matrix for the $π^0$-$η$-$η'$-$a$ system with the linear isospin-breaking effects, is exploited and then implemented to calculate the hadronic form factors relevant to the $τ$ decays. The resonance parameters entering the form factors are determined from fits to the experimental spectra of $τ^- \to π^- π^0 ν_τ$, $τ^- \to K_S π^- ν_τ$, and $τ^- \to K^- ην_τ$. We then focus on the predictions to the branching ratios, invariant-mass distributions, and forward-backward asymmetries from the $τ^-\to P a ν_τ$ processes, with $P=π^-$ and $K^-$. Our results provide a quantitative basis for future searches of the axion-like particle signals in semileptonic $τ$ decays.