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Japanese Journal of Applied Physics

Effects of Reabsorption and Xenon on the Lifetime of the Excited Cesium Atom

Yukio Inoue, Ryuji Iwazaki, Hirokazu Hori, Takeki Sakurai

Published Apr 1, 1988• 1 citation
Publisher

Abstract

The effects of the reabsorption of radiation on the lifetime of the Cs 72P3/2 level were measured from the decaying waveform of fluorescence under various experimental conditions. Reabsorption does not have any influence on the lifetime when the experimental condition satisfies k 0 L<1, where k 0 is the peak absorption coefficient and L is the reabsorbing path length. A theoretical calculation based on a simple model agrees with the experimental results.

DOI
10.1143/jjap.27.445

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The effects of the reabsorption of radiation on the lifetime of the Cs 72P3/2 level were measured from the decaying waveform of fluorescence under various experimental conditions. Reabsorption does not have any influence on the lifetime when the experimental condition satisfies k 0 L<1, where k 0 is the peak absorption coefficient and L is the reabsorbing path length. A theoretical calculation based on a simple model agrees with the experimental results.
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The method of sensitized fluorescence has been employed to investigate the [Formula: see text] excitation transfer processes in cesium induced in collisions with ground state cesium atoms. The cesium vapor density was kept sufficiently low to enable the cross sections for the mixing process to be determined under single collision conditions and to ensure that radiation trapping and quenching were negligible. A nitrogen laser pumped dye laser was used to excite the cesium atoms to each of the 72P levels in turn and measurements of the relative intensities of fluorescence yielded the following cross sections: [Formula: see text] These results are consistent with the empirical relationship between the magnitude of the cross sections and the fine structure splitting that has previously been determined for the alkalis.
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