TEMPERATURE-DEPENDENT DEPOLARIZATION CROSS SECTIONS OF THE 5d6p 3P1 AND 3D1 STATES OF LASER-ABLATED Ba IN He GAS IN THE RANGE 10-300 K. Takashi Nakajima#, Nobuaki Yonekura*, Yukari Matsuo+, Qin Hui+ and Michio Takami+ # Institute of Advanced Energy, Kyoto University, Kyoto 611-0011, Japan *Faculty of Science, University of the Ryukyus, Okinawa 903-0213, Japan +The institute of Physical and Chemical Research (RIKEN), Saitama 351-01, Japan The laser-ablation technique has been applied to the study of depolarization effects of the 5d6p 3P1 and 3D1 states of Ba with He gas in the wide temperature range of 10 -300 K. The depolarization cross sections of both states have been found to have a positive temperature dependence, indicating that the responsible interaction is not a van der Waals type.