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Physical Review A

Formation and mean lifetime of the metastable doubly charged rare-gas dimer NeAr2+

I. Ben-Itzhak, Ilya Gertner, B. Rosner

Published Jan 1, 1993• 16 citations
Publisher

Abstract

The observation of a long-lived ${\mathrm{NeAr}}^{2+}$ molecular ion is reported. This ion was obtained by charge stripping of a 900-keV ${\mathrm{NeAr}}^{+}$ beam in an Ar gas target, and its mean lifetime was determined to be 275\ifmmode\pm\else\textpm\fi{}25 nsec. This is a direct measurement of the mean lifetime of a doubly charged rare-gas dimer. The ion decay is decribed well by a single exponential decay, suggesting that only one metastable state is populated in the collision. The cross section for the ${\mathrm{NeAr}}^{2+}$ production was determined to be (3\ifmmode\pm\else\textpm\fi{}2)\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}18}$ ${\mathrm{cm}}^{2}$. The existence of this weakly bound molecular ion and the fact that its mean lifetime is known can serve to motivate better theoretical calculations of molecular structure and the dissociation process.

DOI
10.1103/physreva.47.289

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