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Branching ratio change in K- absorption at rest and the nature of the Lambda(1405)

A. Ohnishi·Y. Nara·V. Koch
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Abstract

We investigate in-medium corrections to the branching ratio in K- absorption at rest and their effect on the (positively and negatively) charged pion spectrum. The in-medium corrections are due to Pauli blocking, which arises if the Lambda(1405) is assumed to be a $\bar{K}$-nucleon bound state and leads to a density and momentum dependent mass shift of the Lambda(1405). Requiring that the optical potential as well as the branching ratio are derived from the same elementary T-matrix, we find that the in-medium corrected, density dependent T-matrix gives a better description of the K- absorption reaction than the free, density-independent one. This result suggests that the dominant component of the Lambda(1405) wave function is the $\bar{K}N$ bound state.

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A. Ohnishi, Y. Nara, V. Koch. 1997-06-30. Branching ratio change in K- absorption at rest and the nature of the Lambda(1405). https://doi.org/10.1103/physrevc.56.2767

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