Quantum reflection and dwell times of metastable states

TL;DR

This paper extends the concepts of phase and dwell times from tunneling to quantum collisions, establishing a relation that clarifies the behavior of metastable states and quantum reflection in strong interactions.

Contribution

It introduces a new relation between phase and dwell time delays in scattering, extending quantum reflection concepts to strong interactions and addressing near threshold singularities.

Findings

Dwell time delay accurately describes the density of states of metastable states.

The relation removes near threshold s-wave singularities in delay times.

Application to mesic-nuclei metastable states demonstrates the theory's validity.

Abstract

The concept of phase and dwell times used in tunneling is extended to quantum collisions to derive a relation between the phase and dwell time delays in scattering. This relation can be used to remove the near threshold s-wave singularities in the Wigner-Eisenbud delay times and amounts to an extension of the concept of quantum reflection to strong interactions. Dwell time delay emerges as the quantity which gives the correct behaviour of the density of states of a metastable state at all energies. This fact is demonstrated by investigating some recently found metastable states of mesic-nuclei.