Temperature dependence of 3He polarization in aluminum storage cells

Abstract The temperature dependence of the polarization of 3 He atoms in an internal target cell has been studied. Metastable optically pumped polarized 3 He atoms with typical polarization values of 40% were injected into a thin-walled aluminum cell of 40 cm length and a 29.0 × 9.8 mm 2 elliptical cross-section. The cell temperature was varied between 5 and 85 K. The polarization inside the target cell was measured via an asymmetry in the 3 He → (d,p) 4 He reaction at a deuteron energy of 4 MeV. An exponential decrease of the polarization was found for temperatures less than 15 K. For a temperature of ∼6 K a polarization consistent with zero was measured.