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arXiv · 1110.0683

Associative Detachment of H$^{-$ + H $\rightarrow$ H$_{2}$ + e$^{-}$

K. A. Miller·H. Bruhns·J. Eliášek·M. Čížek·H. Kreckel·X. Urbain·D. W. Savin
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Abstract

Using a merged beams apparatus we have measured the associative detachment (AD) reaction of ${\rm H}^- + {\rm H} \to {\rm H}_2 + e^-$ for relative collision energies up to \textit{E}$_{\rm{r}} \leq 4.83$ eV. These data extend above the 1 eV limit of our earlier results. We have also updated our previous theoretical work to account for AD via the repulsive $^2Σ^+_{\rm g}$ H$_2^-$ potential energy surface and for the effects at $E_{\rm r} \ge 0.76$ eV on the experimental results due to the formation of H$_2$ resonances lying above the ${\rm H} + {\rm H}$ separated atoms limit. Merging both experimental data sets, our results are in good agreement with our new theoretical calculations and confirm the prediction that this reaction essentially turns off for $E_{\rm r} \gtrsim 2$ eV. Similar behavior has been predicted for the formation of protonium from collisions of antiprotons and hydrogen atoms.

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K. A. Miller, H. Bruhns, J. Eliášek, M. Čížek, H. Kreckel, X. Urbain, D. W. Savin. 2011-10-04. Associative Detachment of H$^{-$ + H $\rightarrow$ H$_{2}$ + e$^{-}$. https://doi.org/10.1103/physreva.84.052709

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