Measurement and theoretical evaluation of cross section for Na (4D) +Na (3S) →Na (4F) +Na (3S)

Shen Yi-Fan，

Li Wan-Xing，

Polat Ahmat，

Luo Lan

Nuclear Science and Techniques

Vol.8, No.3

pp.157-159

Published in print 01 Aug 1997

47600

Cross section σ_4D→4F was measured for the collision transfer process of Na (4D) + Na (3S) → Na (4F) + Na (3S) . The 4D state is excited by two-photon absorption using a tunable dye laser. Since the 4F→3D fluorescence can not be detected directly with the apparatus used the cascade 3D→3P fluorescence is monitored instead. Then the cross-section σ_4D→4F= (1.3 ± 0.3) ×10^-14cm² is got from the relative intensity of the fluorescence. A theoretical evaluation of σ_4D→4F is also given and compared with experimental results.

Cascade fluorescenceCross sectionLandau-Zener approximation

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