Design of a high density atomic hydrogen source and determination of Balmer cross sections
| Autor: | James D. Walker, Robert M. St. John |
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| Rok vydání: | 1974 |
| Předmět: | |
| Zdroj: | The Journal of Chemical Physics. 61:2394-2407 |
| ISSN: | 1089-7690 0021-9606 |
| DOI: | 10.1063/1.1682333 |
| Popis: | A high density beam of atomic hydrogen was obtained from a Wood discharge and utilized in the measurement of electron‐hydrogen atom collision cross sections. Balmer optical excitation cross sections were determined from observations of crossed electronic and atomic beams. In order to choose Wood discharge parameters to obtain a high degree of dissociation under conditions of a high gas throughput, the differential equations relating the production, loss, and flow of hydrogen atoms and molecules were formulated and solved. The solutions show that recombination of atoms on the metal electrodes greatly reduces the degree of dissociation in large diameter tubes. They further show that this effect can be nearly eliminated by placing short small diameter tubes, called constrictions, between the electrodes and the main tube. A Wood tube 2 cm in diameter and 2 m in length with these constrictions was constructed which produced an atomic to molecular density ratio of 11 at a throughput of 1000 mtorr · liter/sec. T... |
| Databáze: | OpenAIRE |
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