Production of Intense Spin-Polarized Beams of Hydrogen Isotopes by Charge Transfer with High Density Raman-Pumped Alkali-Metal Vapors

TL;DR

This paper proposes a method to generate high-intensity, spin-polarized hydrogen isotope beams using charge transfer in highly polarized cesium vapor, with potential applications in fusion plasma heating.

Contribution

It introduces a novel approach combining Raman-pumped alkali-metal vapors with charge transfer to produce intense polarized hydrogen beams.

Findings

Estimated creation of 80% polarized Cs vapor using Raman pumping.

Potential to produce multi-ampere spin-polarized hydrogen beams.

Application in enhancing fusion plasma heating efficiency.

Abstract

It should be possible to generate multi-ampere spin-polarized beams of hydrogen isotopes by repeated charge-transfer collisions in highly spin-polarized Cs vapor. Estimates suggest that off-resonant Raman pumping with kW scale narrowband tunable light at 895 nm should be able to produce a 1 m long, 10 cm diameter volume of 80\% polarized Cs vapor. The charge transfer collisions between the Cs and hydrogen result in a high nuclear spin-polarized negative ion beam that can be subsequently accelerated to high energy, neutralized, and be used to heat fusion plasmas with resulting increases in the fusion conversion efficiency.