Preservation of ³ He ion polarization after laser-driven acceleration in plasma

The preservation of nuclear spin alignment in plasmas is a prerequisite for important applications, such as energy productionthroughpolarized 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 He target heated by a PW laser pulse, showing evidence consistent with the persistence of nuclear polarization after acceleration to MeV energies via Coulomb explosion of a plasma channel.Our results confirm the theoretically established concept of using pre-polarized targets for experiments in high-power laser facilities.