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Accumulation of three-body resonances above two-body thresholds

Z. Papp·J. Darai·J. Zs. Mezei·Z. T. Hlousek·C-. Y. Hu
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Abstract

We calculate resonances in three-body systems with attractive Coulomb potentials by solving the homogeneous Faddeev-Merkuriev integral equations for complex energies. The equations are solved by using the Coulomb-Sturmian separable expansion approach. This approach provides an exact treatment of the threshold behavior of the three-body Coulombic systems. We considered the negative positronium ion and, besides locating all the previously know $S$-wave resonances, we found a whole bunch of new resonances accumulated just slightly above the two-body thresholds. The way they accumulate indicates that probably there are infinitely many resonances just above the two-body thresholds, and this might be a general property of three-body systems with attractive Coulomb potentials.

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Z. Papp, J. Darai, J. Zs. Mezei, Z. T. Hlousek, C-. Y. Hu. 2004-09-29. Accumulation of three-body resonances above two-body thresholds. https://doi.org/10.1103/physrevlett.94.143201

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