Journal of Physics B Atomic and Molecular Physics

Investigation of excitation transfer processes between hydrogen isotopes by means of laser fluorescence

K. Follmer, K. Bergstedt

Published Mar 14, 1983• 0 citations

Abstract

The hydrogen-deuterium excitation transfer process is investigated experimentally for the case of the n=3 levels. Furthermore, a numerical simulation is provided for testing the method of analysis. The corresponding cross section is evaluated and compared with theoretically calculated values. Results of the numerical simulation are discussed.

DOI: 10.1088/0022-3700/16/5/021

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Journal of Physics B Atomic and Molecular Physics

Investigation of excitation transfer processes between hydrogen isotopes by means of laser fluorescence

K. Follmer, K. Bergstedt

Published Mar 14, 1983• 0 citations

Publisher

Abstract

DOI: 10.1088/0022-3700/16/5/021

Related papers

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Collisional Excitation Transfer between Atoms in the Resonant Process

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Cross sections for energy transfer in collisions between two excited sodium atoms

John Huennekens, Alan Gallagher

We have measured cross sections, ${\ensuremath{\sigma}}_{\mathrm{nL}}$, for the excitation transfer process $\mathrm{Na}(3P)+\mathrm{Na}(3P)\ensuremath{\rightarrow}\mathrm{Na}(3S)+\mathrm{Na}(\mathrm{nL})$, where $\mathrm{nL}$ is the $4D$ or $5S$ level. Our results are ${\ensuremath{\sigma}}_{4D}=23 {\AA{}}^{2}\ifmmode\pm\else\textpm\fi{}35%$ and ${\ensuremath{\sigma}}_{5S}=16 {\AA{}}^{2}\ifmmode\pm\else\textpm\fi{}35%$ at $T\ensuremath{\sim}600$ K. To obtain these cross sections we have used pulsed excitation and measured the intensities of $4D$ , $5S$ , and $3P$ fluorescence emissions, and the spatial distribution of excited atoms resulting from radiation diffusion, as well as the excited atom density as a function of time. Additionally, we have accounted for (time-dependent) radiation trapping of $3P$ and $\mathrm{nL}$ level radiation and for the resulting anisotropies of these fluorescence emissions. Comparisons of our results with theory have been made, and their relevance to other experiments is discussed.We have measured cross sections, ${\ensuremath{\sigma}}_{\mathrm{nL}}$, for the excitation transfer process $\mathrm{Na}(3P)+\mathrm{Na}(3P)\ensuremath{\rightarrow}\mathrm{Na}(3S)+\mathrm{Na}(\mathrm{nL})$, where $\mathrm{nL}$ is the $4D$ or $5S$ level. Our results are ${\ensuremath{\sigma}}_{4D}=23 {\AA{}}^{2}\ifmmode\pm\else\textpm\fi{}35%$ and ${\ensuremath{\sigma}}_{5S}=16 {\AA{}}^{2}\ifmmode\pm\else\textpm\fi{}35%$ at $T\ensuremath{\sim}600$ K. To obtain these cross sections we have used pulsed excitation and measured the intensities of $4D$, $5S$, and $3P$ fluorescence emissions, and the spatial distribution of excited atoms resulting from radiation diffusion, as well as the excited atom density as a function of time. Additionally, we have accounted for (time-dependent) radiation trapping of $3P$ and $\mathrm{nL}$ level radiation and for the resulting anisotropies of these fluorescence emissions. Comparisons of our results with theory have been made, and their relevance to other experiments is discussed.

Physical Review AFeb 1, 198374 citations

The excitation transfer cross sections to several of the excited states of thallium from the

6^{3}P_{1}

and

6^{3}P_{0}

states of mercury have been obtained at various temperatures in the range 800\ifmmode^\circ\else\textdegree\fi{}C to 900\ifmmode^\circ\else\textdegree\fi{}C. Analysis of the equilibrium rates of absorption, emission, and collision processes allows the calculation of excitation transfer cross sections from experimentally determined ratios of intensities of thallium-sensitized fluorescence lines to the intensity of mercury resonance fluorescence, using calculated values of the thallium transition probabilities. The values obtained for the excitation transfer cross sections are comparable in magnitude with collision cross sections based on considerations of gas kinetics.

\mathrm{nL}

is the

4D

5S

level. Our results are ${\ensuremath{\sigma}}_{4D}=23 {\AA{}}^{2}\ifmmode\pm\else\textpm\fi{}35%$ and ${\ensuremath{\sigma}}_{5S}=16 {\AA{}}^{2}\ifmmode\pm\else\textpm\fi{}35%$ at $T\ensuremath{\sim}600$ K. To obtain these cross sections we have used pulsed excitation and measured the intensities of

4D

5S

, and

3P

fluorescence emissions, and the spatial distribution of excited atoms resulting from radiation diffusion, as well as the excited atom density as a function of time. Additionally, we have accounted for (time-dependent) radiation trapping of

3P

and

\mathrm{nL}

level radiation and for the resulting anisotropies of these fluorescence emissions. Comparisons of our results with theory have been made, and their relevance to other experiments is discussed.