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arXiv · 1303.0583

Pressure Dependent Wall Relaxation in Polarized $^3$He Gaseous Cells

C. Peng·W. Zheng·P. -H. Chu·H. Gao·Y. Zhang
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Abstract

Pressure dependence of longitudinal relaxation time (T$_1$) due to the cell wall was observed previously at both room temperature and low temperature in valved Rb-coated refillable $^3$He gaseous cells in \cite{Zheng2}. The diffusion of $^3$He from measurement cell through a capillary tube to the valve and the subsequent depolarization on the surface of the valve was proposed to possibly explain such a pressure dependence at room temperature \cite{Saam}. In this paper, we investigate this diffusion effect through measurements of T$_1$ with newly designed Rb-coated Pyrex glass cells at 295 K as well as finite element analysis (FEA) studies. Both the experimental results and FEA studies show that the diffusion effect is insufficient to explain the observed linear pressure-dependent behavior of T$_1$.

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C. Peng, W. Zheng, P. -H. Chu, H. Gao, Y. Zhang. 2013-03-04. Pressure Dependent Wall Relaxation in Polarized $^3$He Gaseous Cells. https://arxiv.org/abs/1303.0583

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