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

Marie Abboud·Alice Sinatra·Xavier Maitre·Genevieve Tastevin·Pierre-Jean Nacher
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Abstract

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.

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Marie Abboud, Alice Sinatra, Xavier Maitre, Genevieve Tastevin, Pierre-Jean Nacher. 2004-09-22. High nuclear polarization of helium-3 at low and high pressure by metastability exchange optical pumping at 1.5 Tesla. https://doi.org/10.1209/epl%2Fi2004-10237-y

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