Preservation of $^3\mkern-2mu$He ion polarization after laser-plasma acceleration

TL;DR

This paper presents the first experimental evidence that nuclear spin polarization in polarized helium-3 can be preserved after laser-plasma acceleration to MeV energies, supporting its use in high-power laser experiments.

Contribution

First experimental confirmation of helium-3 nuclear polarization preservation after laser-driven plasma acceleration.

Findings

Nuclear polarization persists after acceleration to MeV energies.

Supports use of pre-polarized targets in high-power laser experiments.

Validates theoretical assumptions about spin conservation in plasma conditions.

Abstract

The preservation of nuclear spin alignment in plasmas is a prerequisite for important applications, such as energy production through polarized fusion or the acceleration of polarized particle beams. Although this conservation property has been the basis of numerous theoretical papers, it has never been experimentally confirmed. Here, we report on first experimental data from a polarized $^3\mkern-2mu$He target heated by a PW laser pulse, showing evidence for persistence of the nuclear polarization after acceleration to MeV energies. The finding also validates the concept of using pre-polarized targets for experiments at high-power laser facilities.