利用时间分辨光谱技术, 研究了激光诱导Cu等离子体中激发态4d′ 4F9/2的形成及其辐射跃迁的瞬态特性。结果表明: 电子离子复合、粒子间碰撞、自蚀吸收等过程在等离子体不同演化时刻, 对激发态4d′ 4F9/2原子的制备起着不同作用。粒子间碰撞作用剧烈时, 激发态4d′ 4F9/2原子以相同几率向低能态4p′ 4Do7/2及4p′ 4Fo9/2跃迁转移能量; 等离子体辐射约500 ns后, 粒子间相互作用变弱, 激发态4d′ 4F9/2原子主要通过辐射谱线Cu Ⅰ 359.91 nm转移能量。

The formation of copper excited state 4d′ 4F9/2 and its transition in the copper plasma induced by laser are studied by the time-resolved spectra technology. The experimental results indicate that the formation of excited state 4d′ 4F9/2 follows different mechanisms, such as recombination of electrons and ions, collision between the elemental species and self-absorption of atomic lines, during the evolution of plasma. When the collision between particles is severe, the excited state 4d′ 4F9/2 transits to low energy states 4p′ 4Do7/2 and 4p′ 4Fo9/2 with the same probability. After 500 ns of plasma radiation, the collision becomes weak, and the excited state 4d′ 4F9/2 mainly transits to 4p′ 4Do7/2 with emitting the characteristic line Cu Ⅰ 359.91 nm.