Critical review of deeply bound kaonic nuclear states

TL;DR

This paper critically examines recent claims of deeply bound kaonic nuclear states, arguing that current experimental evidence is unconvincing and that observed peaks can be explained by conventional nuclear processes.

Contribution

The paper provides a detailed critique of experimental claims, demonstrating that observed signals are consistent with known nuclear absorption and final-state interactions rather than new bound states.

Findings

No convincing experimental evidence for deeply bound kaonic states.

Observed peaks can be explained by two-nucleon absorption processes.

Final-state interactions account for the spectral features.

Abstract

We critically revise the recent claims of narrow deeply bound kaonic states and show that at present there is no convincing experimental evidence for their existence. In particular, we discuss in details the claim of K- pp deeply bound state associated to a peak seen in the Lambda p invariant mass spectrum from K- nuclear absorption reactions by the FINUDA collaboration. An explicit theoretical simulation shows that the peak is simply generated from a two-nucleon absorption process, like K- pp --> Lambda p, followed by final-state interactions of the produced particles with the residual nucleus.