Diffusion cross-section in system with atom resonance excitation

S. M. Bortsaǐkin, L. P. Kudrin, Yu. V. Mikhaǐlova

Yu. M. Smirnov

Moncef Bouledroua, A. Dalgarno, Robin Côté

We report calculations of diffusion, excitation transfer, width, and shift cross sections. We use these cross sections to obtain the diffusion coefficient and the width and line shift due to collisions of alkali-metal atoms in the impact approximation. The results are compared to analytical expressions obtained from semiclassical treatments, and with measured widths for sodium atoms. Extension to other alkali metal atoms is also given.

Edward M. D'Arcy

SHEN YI-FAN, LI WAN-XING, 新疆大学物理系,乌鲁木齐830046

Two different atomic species-sodium and cesium-have been resonantly excited in a cell by a cw dye laser and a cesium lamp, respectively. The density of the excited Na(3P) atoms in the cell is measured directly using the absorption-equivalent-width technique on the lines of the diffuse series. To isolate the heteronuclear contribution in the fluorescence spectrum, a modulation detection technique has been adopted. The energy-pooling collisions between Na(3P) and Cs(6P) have been observed and cross sections have been measured.

M. Czajkowski, Andrzej Baczyński, L. Krause