Measuring the enhancement factor of the hyperpolarized Xe in nuclear magnetic resonance gyroscopes

In atomic gyroscopes, measuring the effective noble-gas magnetic field enables the determination of the noble-gas polarization. The enhancement factor is introduced to relate the effective magnetic field and the polarization in a certain magnetic-field environment. Earlier experiments concentrate on the strong magnetic-field environment for measuring the spin-exchange cross section precisely, so the results on the enhancement factor in the weak magnetic field are still insufficient. In our nuclear magnetic resonance gyroscope based on Cs-Xe129 and -Xe131, the magnetic field is usually set to 1-10 μT. In this paper, we measure the effective magnetic field and the polarization of Xe atoms to estimate the Cs-Xe enhancement factor in the weak magnetic field of 2.5 μT and give the estimation of the Cs-Xe129 enhancement factor of (1.60±0.06)×104.