Scattering of positronium from singly ionized helium and appearing resonances

P K Biswas; H. M. Gupta

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arXiv · physics/0106041

Scattering of positronium from singly ionized helium and appearing resonances

P K Biswas·H. M. Gupta

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Abstract

The coupled-channel model [Phys. Rev. A {\bf 59}, 363 (1999)] that yields converged low-energy phase shifts, and exact binding and resonance features in Ps-H [Phys. Rev. A {\bf 59}, 2058 (1999)] is applied to study Ps-He$^+$ scattering. Similar to PsH, resonances appear in the S-, P-, D-, etc partial waves in the Ps-He$^+$ system but in both the singlet and triplet scattering channels. The latter signifies possible Rydberg states of $e^+$ around singlet and triplet helium. The S-wave singlet resonance at 2.79 eV agrees to that predicted earlier in $e^+$-He entrance channel (energy difference 16.64 eV) at 19.27 eV [Chem. Phys. Lett. {\bf 262}, 460 (1996)].

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P K Biswas, H. M. Gupta. 2001-06-13. Scattering of positronium from singly ionized helium and appearing resonances. https://arxiv.org/abs/physics/0106041

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