High nuclear polarization of helium-3 at low and high pressure by metastability exchange optical pumping at 1.5 Tesla

Marie Abboud (1) , Alice Sinatra (1) , Xavier Maître (2) , Geneviève Tastevin (1) , Pierre-Jean Nacher (1)

1 LKB (Lhomond) - Laboratoire Kastler Brossel
2 U2R2M - Unite de recherche en résonance magnétique médicale

We perform metastability exchange optical pumping of helium-3 in a strong magnetic field of 1.5 T. The achieved nuclear polarization, from 80% at 1.33 mbar to 25% at 67 mbar, shows a substantial improvement at high pressures with respect to standard low-field optical pumping. The specific mechanisms of metastability exchange optical pumping at high field are investigated, advantages and intrinsic limitations are discussed. From a practical point of view, our results open the way to alternative technological solutions for polarized helium-3 applications and in particular for magnetic resonance imaging of human lungs.

Mots clés: magnetic resonance imaging with polarized gases.; metastability exchange optical pumping; polarized helium-3; magnetic resonance imaging with polarized gases

Domaines: Physique Atomique [physics.atom-ph]

Marie Abboud, Alice Sinatra, Xavier Maître, Geneviève Tastevin, Pierre-Jean Nacher. High nuclear polarization of helium-3 at low and high pressure by metastability exchange optical pumping at 1.5 Tesla. 2003. ⟨hal-00000535v1⟩