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arXiv · 1401.7774

Slow and velocity-tunable beams of metastable He$_2$ by multistage Zeeman deceleration

Michael Motsch·Paul Jansen·Josef A. Agner·Hansjürg Schmutz·Frédéric Merkt
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Abstract

Metastable helium molecules (He$_2^*$) have been generated by striking a discharge in a supersonic expansion of helium gas from a pulsed valve. When operating the pulsed valve at room temperature, 77K, and 10K, the mean velocity of the supersonic beam was measured to be 1900m/s, 980m/s, and 530m/s, respectively. A 55-stage Zeeman decelerator operated in a phase-stable manner was then used to further reduce the beam velocity and tune it in the range between 100 and 150m/s. The internal-state distribution of the decelerated sample was established by photoionization spectroscopy.

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Michael Motsch, Paul Jansen, Josef A. Agner, Hansjürg Schmutz, Frédéric Merkt. 2014-01-30. Slow and velocity-tunable beams of metastable He$_2$ by multistage Zeeman deceleration. https://doi.org/10.1103/physreva.89.043420

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