Metastability exchange optical pumping of $^3$He at low pressure and high magnetic field

TL;DR

This study investigates metastability exchange optical pumping of helium-3 at low pressure and high magnetic fields, achieving high nuclear polarization and informing the development of polarized helium-3 targets for experimental physics.

Contribution

It systematically explores the effects of various parameters on helium-3 polarization at high magnetic fields, providing new insights for polarized target development.

Findings

Maximum nuclear polarization of about 75% achieved.

Optimal conditions depend on discharge intensity, laser power, and transition schemes.

Baseline data established for future polarized helium-3 target design.

Abstract

Systematic studies on metastability exchange optical pumping of $^3$He nuclei have been performed at Jefferson Lab using a 1-torr sealed cell at magnetic fields from 2 to 4 T. The effects of the discharge intensity, pump laser power, and pumping transition schemes on achievable nuclear polarization and pumping rate have been investigated. A maximum steady-state nuclear polarization of about 75% has been obtained. This work provides a baseline for the development of the novel polarized $^3$He target for CLAS12 at Jefferson Lab.