Lambda(1405) N to Y N transition in nuclear medium for non-mesonic absorption of Kbar in nucleus

TL;DR

This paper investigates the non-mesonic transition of Lambda(1405) N to YN in nuclear matter, highlighting the dependence on coupling ratios and estimating decay widths relevant for Kbar absorption in nuclei.

Contribution

It introduces a model-based analysis of Lambda(1405) N to YN transitions, emphasizing the role of coupling ratios and providing decay width estimates in nuclear matter.

Findings

The transition ratio Gamma_{Lambda N} / Gamma_{Sigma N} depends strongly on Lambda^*-Kbar N coupling.

A larger Lambda^*-Kbar N coupling enhances the Lambda N transition.

Total non-mesonic decay width of Lambda^* in nuclear matter is approximately 22 MeV.

Abstract

Non-mesonic transition of Lambda(1405) N to YN is investigated as one of the essential processes for the non-mesonic absorption of Kbar in nuclei. Using one-meson exchange model in the calculation of the transition, we find that the non-mesonic transition ratio Gamma_{Lambda N} / Gamma_{Sigma N} depends strongly on the ratio of the Lambda(1405) (Lambda^*) couplings to Kbar N and pi Sigma. Especially a larger Lambda^*-Kbar N coupling leads to enhancement of the transition to Lambda N. Using the chiral unitary model for the description of the Lambda^*, we obtain Gamma_{Lambda N} / Gamma_{Sigma^{0} N} is approximately 1.2 which is almost independent of the nucleon density, and find the total non-mesonic decay width of the Lambda^* in uniform nuclear matter to be 22 MeV at the normal density.