高温辐射场作用下的原子过程

Atomic process in high-temperature radiation field

等离子体中辐射能量密度与物质能量密度的比值是区分等离子体原子过程性质的重要参量.根据这个参量,等离子体中的原子过程可分为碰撞占优和辐射占优两种典型类型.数值模拟发现碰撞占优和辐射占优的原子过程有不同的性质:碰撞占优的等离子体能够很快达到LTE状态;辐射占优等离子体的束缚电子温度、电离度和自由电子温度存在不同的弛豫时间尺度,存在某种形式的准平衡状态.

The ratio of radiation energy density to matter energy density is an important parameter to distinguish the characteristic of atomic processes in plasma.Actoring to this parameter,atomic processes in plasma can be divided into two typical categories：collision-dominated and radiation-dominated.According to numerical simulation,atomic processes of these two categories have different characteristics.The LTE state can be quickly reached in the collision-dominated plasma.However in the radiation-dominated plasma, the temperature of bound electrons,the ionization degree,and the temperature of free electrons have different relaxation time scales. There is some kind of quasi-LTE state.