# $\Xi(1690)^-$ resonance production via $K^-p \to K^+K^-\Lambda$

## TL;DR

This study models the production of the $ ext{Xi}(1690)^-$ resonance in $K^-p$ reactions using an effective Lagrangian approach, providing predictions for cross sections and Dalitz plots to guide future experiments.

## Contribution

It introduces a detailed theoretical model including various channels for $ ext{Xi}(1690)^-$ production and offers predictions for experimental observables near threshold energies.

## Key findings

- Computed Dalitz plot densities at 4.2 GeV/c.
- Predicted total and two-body cross sections.
- Suggested experimental conditions for observing $ ext{Xi}(1690)^-$.

## Abstract

In this talk, we investigate $\Xi(1690)^-$ production from the $K^-p\to K^+K^-\Lambda$ reaction wit the effective Lagrangian method and consider the $s$- and $u$-channel $\Sigma/\Lambda$ ground states and resonances for the $\Xi$-pole contributions, in addition to the $s$-channel $\Lambda$, $u$-channel nucleon pole, and $t$-channel $K^-$-exchange for the $\phi$-pole contributions. The $\Xi$-pole includes $\Xi(1320)$, $\Xi(1535)$, $\Xi(1690)(J^p=1/2^-)$, and $\Xi(1820)(J^p=3/2^-)$. We compute the Dalitz plot density of $(d^2\sigma/dM_{K^+K^-}dM_{K^-\Lambda}$ at 4.2 GeV$/c$) and the total cross sections for the $K^-p\to K^+K^-\Lambda$. Employing the parameters from the fit, we present the cross sections for the two-body $K^-p\to K^+\Xi(1690)^-$ reaction near the threshold. We also demonstrate that the Dalitz plot analysis for $p_{K^-}=1.915 \sim2.065$ GeV/c makes us to explore direct information for $\Xi(1690)^-$ production, which can be done by future $K^-$ beam experiments.