Energy-Transfer Processes of Xe (6p1/2_\textbf0, 6p3/2_\textbf2, and 6p5/2_\textbf2) Atoms under the Condition of Ultrahigh Pumped Power

The kinetic processes of Xe (6p1/2_0, 6p3/2_2, and 6p5/2_2) atoms under the focused condition were investigated. The atomic density of the laser prepared state significantly increases. Therefore, the probability of the energy-pooling between two high-lying atoms increases. There are three major types of the energy-pooling collisions. The first type is the energy-pooling ionization. Once the excitation laser is focused, the obvious ionization can be observed from the side window whenever the laser prepared state is 6p1/2_0, 6p3/2_2, or 6p5/2_2 state. Ionization of Xe is attributed to the energy-pooling ionization or a Xe^* atom reabsorbing another excitation photon. The second type is energy-pooling with big energy difference. When the 6p1/2_0 state is the laser prepared state, the energy-pooling collision between two 6p1/2_0 atoms can produce one 5d3/2_1 atom and one 6s'1/2_0 atom. The third type is energy-pooling with small energy difference. The intensities of fluorescence lines are much stronger that five secondary 6p states act as the upper states, and the rising edges of these fluorescence lines are much steeper. The primary mechanism of generating the secondary 6p atoms is energy-pooling collision instead of collision relaxation. Based on the collision probability, the rate of energy-pooling between two 6p1/2_0 atoms is deduced (6.39\times10^8 s^-1). In addition, the 6s atoms also increase under the focused condition. Therefore, all the fluorescence lines are serious trailing by radiation trapping.