Ultracold homonuclear and heteronuclear collisions in metastable helium
| Autor: | Daniel Cocks, G Peach, Ian B. Whittingham |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2019 |
| Předmět: |
Physics
Condensed Matter::Quantum Gases Atomic Physics (physics.atom-ph) Scattering FOS: Physical sciences chemistry.chemical_element Atmospheric temperature range 01 natural sciences Homonuclear molecule 010305 fluids & plasmas Physics - Atomic Physics chemistry Heteronuclear molecule Ionization Metastability 0103 physical sciences Physics::Atomic and Molecular Clusters Physics::Atomic Physics Atomic physics 010306 general physics Helium Electrostatic interaction |
| Popis: | Scattering and ionizing cross sections and rates are calculated for ultracold collisions between metastable helium atoms using a fully quantum-mechanical close-coupled formalism. Homonuclear collisions of the bosonic ${}^{4}$He$^{*} +{}^{4}$He$^{*}$ and fermionic ${}^{3}$He$^{*} + {}^{3}$He$^{*}$ systems, and heteronuclear collisions of the mixed ${}^{3}$He$^{*} +{}^{4}$He$^{*}$ system, are investigated over a temperature range 1 $\mu$K to 1 K. Carefully constructed Born-Oppenheimer molecular potentials are used to describe the electrostatic interaction between the colliding atoms, and complex optical potentials used to represent loss through ionization from the ${}^{1,3}\Sigma $ states. Magnetic spin-dipole mediated transitions from the ${}^{5}\Sigma $ state are included and results reported for spin-polarized and unpolarized systems. Comparisons are made with experimental results, previous semi-classical models, and a perturbed single channel model. Comment: 14 pages, 9 figures |
| Databáze: | OpenAIRE |
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