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arXiv · 1310.1511

Ion neutralisation mass-spectrometry route to radium monofluoride (RaF)

T. A. Isaev·S. Hoekstra·L. Willmann·R. Berger
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Abstract

The diatomic molecule radium monofluoride (RaF) has recently been proposed as a versatile probe for physics beyond the current standard model. Herein, a route towards production of a RaF molecular beam via radium ions is proposed. It takes advantage of the special electronic structure expected for group 2 halides and group 2 hydrides: The electronic ground state of neutral RaF and its monocation differ in occupation of a non-bonding orbital of $σ$ symmetry. This implies similar equilibrium distances and harmonic vibrational wavenumbers in the two charge states and thus favourable Franck--Condon factors for neutralisation without dissociation in neutralising collisions. According to the calculated ionisation energy of RaF, charge exchange collisions of RaF$^+$ with sodium atoms are almost iso-enthalpic, resulting in large cross-sections for the production of neutral radium monofluoride.

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T. A. Isaev, S. Hoekstra, L. Willmann, R. Berger. 2013-11-21. Ion neutralisation mass-spectrometry route to radium monofluoride (RaF). https://arxiv.org/abs/1310.1511

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