The Lambda* N interaction and two-body bound state based on chiral dynamics

TL;DR

This paper investigates the Lambda*(1405)-nucleon interaction using chiral dynamics, constructing a meson-exchange potential, and finds a quasi-bound state below threshold with implications for Lambda*-hypernuclei.

Contribution

It introduces a coordinate space Lambda* N potential based on chiral dynamics and solves the coupled-channel system to identify a quasi-bound state, advancing understanding of Lambda*-hypernuclei.

Findings

Identification of a s-wave quasi-bound state below threshold in the S=0 channel.

Demonstration of the significance of Kbar exchange in the Lambda* N potential.

Analysis of the finite width due to coupling to lower energy channels.

Abstract

The interaction of Lambda*=Lambda(1405) with a nucleon is studied from the viewpoint of chiral dynamics. We construct the coordinate space Lambda* N potential in the meson-exchange picture, which serves as a fundamental ingredient for the study of the few-body nuclear systems with a Lambda*, the Lambda*-hypernuclei. The coupling constants concerning Lambda* are determined based on the chiral unitary model picture for the meson-baryon scattering where Lambda* is described as a superposition of two resonance poles. Solving the coupled-channel two-body Lambda* N system, we find the higher energy Lambda* N state develops an s-wave quasi-bound state slightly below the threshold in the total spin S=0 channel, which acquires a finite width through the coupling to the lower energy Lambda* N channel. We show important roles of the Kbar exchange contribution to the Lambda* N potential.