Effective field theory for triaxially deformed odd-mass nuclei

TL;DR

This paper extends effective field theory to describe collective rotations in triaxially deformed odd-mass nuclei, improving the modeling of wobbling bands by including next-to-leading order corrections.

Contribution

It introduces a generalized Hamiltonian for odd-mass nuclei within effective field theory, incorporating higher-order corrections to better match experimental wobbling energies.

Findings

Next-to-leading order corrections improve wobbling energy predictions.

The model accurately describes spin-rotational frequency relations.

Application to lutetium isotopes demonstrates enhanced agreement with data.

Abstract

The effective field theory for collective rotations of triaxially deformed nuclei is generalized to odd-mass nuclei by including the angular momentum of the valence nucleon as an additional degree of freedom. The Hamiltonian is constructed up to next-to-leading order within the effective field theory formalism. The applicability of this Hamiltonian is examined by describing the wobbling bands observed in the lutetium isotopes $^{161,163,165,167}$Lu. It is found that by taking into account the next-to-leading order corrections, quartic in the rotor angular momentum, the wobbling energies $E_{\textrm{wob}}$ and spin-rotational frequency relations $\omega(I)$ are better described than with the leading order Hamiltonian.