Angular Momentum-Resolved Inelastic Electron Scattering for Nuclear Giant Resonances

TL;DR

This paper develops a new theoretical framework for inelastic electron scattering that resolves angular momentum transfer, enabling detailed study of nuclear giant resonances using plane-wave and vortex electrons with potential applications in nuclear physics and particle generation.

Contribution

It introduces a comprehensive angular momentum-resolved inelastic electron scattering theory, allowing extraction of transition strengths and efficient generation of vortex electrons for nuclear resonance studies.

Findings

Plane-wave electrons can extract transition strengths of higher multipolarity.

Vortex electrons with OAM ±1 can be efficiently generated and used for resonance analysis.

The method is robust regardless of the nucleus position relative to the beam axis.

Abstract

Giant resonances (GRs) provide crucial insights into nuclear physics and astrophysics. Exciting GRs using particles like electrons is effective, yet the angular momentum (AM) transfer of electrons, including both intrinsic spin and orbital degrees of freedom in inelastic scattering, has never been studied. Here, we investigate AM transfer in GRs excited by plane-wave and vortex electrons, developing a comprehensive AM-resolved inelastic electron scattering theory. We find that even plane-wave electrons can model-independently extract transition strengths of higher multipolarity by selecting specific AM states of scattered electrons. Additionally, relativistic vortex electrons with orbital angular momentum (OAM) $\pm1$ can be efficiently generated. Vortex electrons can also be used to extract GR transition strength as in the plane-wave case, regardless of the position of nucleus relative to the beam axis. Furthermore, relativistic vortex electrons with larger OAM can be generated for on-axis nuclei due to AM conservation. Our method offers new perspectives for nuclear structure research and paves the way for generating vortex particles.