Role of $\Sigma(1660)$ in the $K^- p \to\pi^0\pi^0\Sigma^0$ reaction

TL;DR

This study investigates the role of the $ ext{Σ}(1660)$ resonance in specific kaon-proton reactions, demonstrating its necessity for accurately reproducing experimental data and suggesting these measurements can help determine its properties.

Contribution

The paper introduces the inclusion of the $ ext{Σ}(1660)$ resonance in modeling the reactions, providing a better fit to experimental data and highlighting its significance in these processes.

Findings

The $ ext{Σ}(1660)$ resonance is essential for reproducing experimental cross sections.

Model successfully fits data for both reactions with the resonance included.

Experimental data can help determine properties of the $ ext{Σ}(1660)$ resonance.

Abstract

The processes of $K^-p \to \pi^0 \pi^0 \Sigma^0$ and $K^- p \to \pi^0 \Lambda(1405)$ are studied within the effective Lagrangian approach. In addition to the ``background" contribution from the $u$-channel nucleon pole term, contribution from the $\Sigma(1660)$ resonance with spin-parity $J^P=1/2^+$ is also considered. For the $K^-p \to \pi^0 \pi^0 \Sigma^0$ reaction, we perform a calculation for the total and differential cross sections by considering the contribution from the $\Sigma(1660)$ intermediate resonance decaying into $\pi^0 \Lambda(1405)$ with $\Lambda(1405)$ decaying into $\pi^0 \Sigma^0$. With our model parameters, the available experimental data on both the $K^-p \to \pi^0 \pi^0 \Sigma^0$ and $K^- p \to \pi^0 \Lambda(1405)$ reactions can be fairly well reproduced. It is shown that we really need the contribution from the $\Sigma(1660)$ resonance, and that these experimental measurements could be used to determine some properties of the $\Sigma(1660)$ resonance.