氙气中辐射激波的发光特性  

Radiation properties of radiative shock in xenon

作　　者：赵多 李守先[1] 安建祝[1,2] 吴勇 吴泽清[1] 李琼[1] 王芳[1] 孟广为 Zhao Duo;Li Shou-Xian;An Jian-Zhu;Wu Yong;Wu Ze-Qing;Li Qiong;Wang Fang;Meng Guang-Wei(Institute of Applied Physics and Computational Mathematics,Beijing 100094,China;Center for Applied Physics and Technology,Peking University,Beijing 100871,China)

机构地区：[1]北京应用物理与计算数学研究所,北京100094 [2]北京大学应用物理与技术研究中心,北京100871

出　　处：《物理学报》2021年第7期206-214,共9页Acta Physica Sinica

摘　　要：本文模拟研究了氙气中X射线加热产生辐射激波的发光特性.辐射激波采用Zinn模型计算,并在模型中输入氙气的辐射不透明度和状态方程参数.研究发现,辐射激波伴随着丰富的光学演化过程,激波对外辐射强度表现出两个明显的亮度峰值和一个亮度极小值,辐射光谱也经常偏离黑体辐射光谱.对氙气不同位置光学特性的分析可知,激波和内部高温区的辐射吸收系数的动态演化导致了辐射激波的发光位置和辐射强度的变化.Radiative shock is an important phenomenon both in astrophysics and in inertial confinement fusion.In this paper,the radiation properties of X-ray heated radiatve shock in xenon is studied with the simulation method.The radiative shock is described by a one-dimensional,multi-group radiation hydrodynamics model proposed by Zinn[Zinn J 1973 J.Comput.Phys.13569].To conduct computation,the opacity and equation-ofstate data of xenon are calculated and put into the model.The reliabilities of the model and the physical parameters of xenon are verified by comparing the temperature and velocity of the radiative shock calculated by the model with those measured experimentally.The evolution of the radiative shock involves abundant physical processes.The core of the xenon can be heated up to 100 eV,resulting in a thermal wave and forming an expanding high-temperature-core.Shortly,the hydrodynamic disturbances reach the thermal wave front,generating a shock.As the thermal wave slows down,the shock gradually exceeds the high-temperature-core,forming a double-step distribution in the temperature profile.The time evolution of the effective temperature of the radiative shock shows two maximum values and one minimum value,and the radiation spectra often deviate from blackbody spectrum.By analyzing the radiation and absorption properties at different positions of the shock,it can be found that the optical property of the shock is highly dynamic and can generate the above-mentioned radiation characteristics.When the radiative shock is just formed,the radiation comes from the shock surface and the shock precursor has a significant absorption of the radiation.As the shock temperature falls during expansion,the shock precursor disappears and the radiation inside the shock can come out owing to absorption coefficient decreases.When the shock becomes transparent,the radiation surface reaches the outside edge of the high-temperature-core.Then,the temperature of the high-temperature-core decreases further,making this region also optically

关 键 词：辐射激波 辐射光谱 氙气 辐射流体力学 

分 类 号：O354.5[理学—流体力学]