Kinetics of Rb2+ and Rb+ formation in laser-excited rubidium vapor

• Authors: Mohamed Mahmoud
• Languages of publication: EN

Abstracts

EN

We have studied the formation of the molecular ion Rb2+ and the atomic ion Rb+. These are created in laser excited rubidium vapor at the first resonance, 5s–5p and 5p-nl transitions. A theoretical model is applied to this interaction to explain the time evolution and the laser-power dependence of the population density of Rb+ and Rb2+. A set of rate equations which describe: the temporal variation of the population density of the excited states; the atomic ion density; and the electron density, were solved numerically under the experimental conditions of Barbier and Cheret. In their experiment the Rb concentration was 1×1013cm−3 and the laser power was taken to be 50–500 mW at vapor temperature = 450 K. The results showed that the main processes for producing Rb2+ are associative ionization and Hornbeck-Molnar ionization. The calculations have also showed that, the atomic ions Rb+ are formed through the Penning Ionization (PI) and photoionization processes. Moreover, a reasonable agreement between the experimental results and our calculations for the ion currents of the Rb+ and Rb2+ is obtained.

Keywords

EN

penning ionization; associative ionization; Molnar-Hornbeck ionization; plasma, laser

Discipline

• 34.80.Dp: Atomic excitation and ionization
• 34.50.Fa: Electronic excitation and ionization of atoms (including beam-foil excitation and ionization)

• Publisher: De Gruyter Open
• Journal: Open Physics
• Year: 2008
• Volume: 6
• Issue: 3
• Pages: 530-538

Dates

published

1 - 9 - 2008

online

17 - 7 - 2008

Contributors

author

Mohamed Mahmoud

• Physics department, Faculty of Science, Sohag University, 82524, Sohag, Egypt

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Identifiers

DOI

10.2478/s11534-008-0074-5