Polarizing 3He via Metastability Exchange Optical Pumping Using a 1.2 mbar Sealed Cell at Magnetic Fields up to 5 T

TL;DR

This study demonstrates high nuclear polarization of 3He gas using Metastability Exchange Optical Pumping in a sealed cell at magnetic fields up to 5 T, enabling advanced neutron studies in nuclear physics.

Contribution

It presents the first high-field (up to 5 T) nuclear polarization of 3He gas in a sealed cell using MEOP, with systematic analysis of parameters affecting polarization.

Findings

Achieved 86% polarization at 2-5 T magnetic fields.

Discharge-on relaxation time measured at 898 seconds at 5 T.

Identified optimal conditions for high polarization in strong magnetic fields.

Abstract

We report high nuclear polarization of 1.2 mbar 3He gas in a sealed cell in magnetic fields up to 5 T using Metastability Exchange Optical Pumping (MEOP). The creation of a highly polarized 3He gas target for use in the 5 T field of Jefferson Lab's CLAS12 spectrometer would enable new studies of spin-dependent asymmetries on the neutron. A systematic study was conducted to evaluate the effects of discharge intensity, pump laser power, and optical pumping transition schemes on nuclear polarization and pumping rates. Steady-state polarizations up to 86 % in magnetic fields between 2 and 5 T were achieved, with a discharge-on relaxation time of 898 s at 5 T. These results underscore the potential of MEOP for high-field applications in nuclear physics experiments.