Unitary correlation in nuclear reaction theory

TL;DR

This paper proves that certain nuclear reaction amplitudes remain unchanged under unitary correlation operators, showing they are independent of spectroscopic factors, which are not suitable for extracting these amplitudes.

Contribution

It demonstrates the invariance of reaction amplitudes under unitary correlations and clarifies that spectroscopic factors do not parametrize these amplitudes.

Findings

Reaction amplitudes are invariant under unitary correlation operators.

Spectroscopic factors do not determine the exact reaction amplitudes.

Reaction amplitudes cannot be used to extract spectroscopic factors.

Abstract

We prove that the amplitudes for the (d,p), (d,pn) and (e,e'p) reactions determining the asymptotic behavior of the exact scattering wave functions in the corresponding channels are invariant under unitary correlation operators while the spectroscopic factors are not. Moreover, the exact reaction amplitudes are not parametrized in terms of the spectroscopic factors and cannot provide a tool to determine the spectroscopic factors.