15min:

FENG XIE, DAN LI, LI LI, Department of Physics and Key Laboratory of Atomic and Molecular Nanosciences, Tsinghua University,Beijing 100084, China; VLADIMIR B. SOVKOV, VALERY S. IVANOV, V. A. Fock Institute of Physics, St. Petersburg State University, 1 Ulyanovskaya Street, Petrodvorets, St. Petersburg 198504, Russia; AND SYLVIE MAGNIER, Laboratoire de Physique des Atomes, Lasers, Molećule et Surfaces (PALMS), CNRS et Universite\' RENNES I (UMR 6627), Campus de Beaulieu, Bt 11B 35042 Cedex, France.

Fifty 3³ _g⁺ v =2-9 X ¹ _g⁺ two-photon transitions of Cs₂ have been observed in the infrared wavelength. Vibrational resolved fluorescence into both bound levels and the continuum of the a ³ _u⁺ state has been recorded with~monochromator. Calculated 3³ _g⁺ a ³ _u⁺ fluorescence spectra are compared with observed spectra.

With two infrared diode lasers,totally 43 ro-vibrational levels of the Cs₂ 3³ _g state have been observed by perturbation facilitated infrared-infrared double resonance spectroscopy. Rotationally resolved fluorescence to the a ³ _u⁺ state was also recorded.