Positive and negative parity states of the Two-Rotor Model and scissors modes

TL;DR

This paper extends the Two-Rotor Model by allowing wave functions to have negative parity states, revealing a richer spectrum split by tunneling effects, thus enhancing understanding of rotor symmetries and scissors modes.

Contribution

It introduces a relaxation of symmetry constraints in the Two-Rotor Model, enabling the study of both positive and negative parity states and their tunneling-induced splitting.

Findings

Positive and negative parity states are both present in the extended model.

Tunneling effects cause splitting of these states.

The model provides a more complete description of scissors modes.

Abstract

In previous investigations of the Two-Rotor Model with axially symmetric rotors the wave functions were assumed to be invariant under inversion of the axes of the rotors, which restricted the spectrum to positive parity states. We relax this condition requiring only that the wave functions be invariant under the square of the inversion operators. As a result we get positive as well as negative parity states that are all split by tunneling effect.