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arXiv · physics/9805033

Antiproton-Hydrogen annihilation at sub-kelvin temperatures

A. Yu. Voronin·J. Carbonell
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Abstract

The main properties of the interaction of ultra low-energy antiprotons ($% E\le10^{-6}$ a.u.) with atomic hydrogen are established. They include the elastic and inelastic cross sections and Protonium (Pn) formation spectrum. The inverse Auger process ($Pn+e \to H+\bar{p}$) is taken into account in the framework of an unitary coupled-channels model. The annihilation cross-section is found to be several times smaller than the predictions made by the black sphere absorption models. A family of $\bar{p}H$ nearthreshold metastable states is predicited. The dependence of Protonium formation probability on the position of such nearthreshold S-matrix singularities is analysed. An estimation for the $H\bar{H}$ annihilation cross section is obtained.

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A. Yu. Voronin, J. Carbonell. 1998-05-24. Antiproton-Hydrogen annihilation at sub-kelvin temperatures. https://doi.org/10.1103/physreva.57.4335

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