arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 0903.0466physics.plasm-ph
收藏

具有密度和温度梯度的稠密等离子体中的汤姆逊散射

Thomson scattering in dense plasmas with density and temperature gradients

C. Fortmann, R. Thiele, R. R. Fäustlin, Th. Bornath, B. Holst, W. -D. Kraeft, V. Schwarz, S. Toleikis, Th. Tschentscher, R. Redmer

摘要:

集体X射线汤姆逊散射已成为诊断稠密等离子体的通用工具。假设整个目标样品的密度和温度均匀,这些参数可以通过细致平衡直接从等离子体激元色散和等离子体激元振幅的比率确定。在非均匀介质中,散射信号是与密度和温度分布加权的密度和温度相关的散射截面的平均值。本文分析了自由电子激光辐射近固体密度氢靶产生的超紫外汤姆逊散射谱,通过比较密度和温度平均散射信号与假设均匀靶的计算结果,研究了等离子体不均匀性对散射谱的影响。我们发现平均电子密度和有效密度之间以及平均温度和有效温度之间的差异大于10%。

英文摘要:

Collective X-ray Thomson scattering has become a versatile tool for the diagnostics of dense plasmas. Assuming homogeneous density and temperature throughout the target sample, these parameters can be determined directly from the plasmon dispersion and the ratio of plasmon amplitudes via detailed balance. In inhomogeneous media, the scattering signal is an average of the density and temperature dependent scattering cross-section weighted with the density and temperature profiles. We analyse Thomson scattering spectra in the XUV range from near solid density hydrogen targets generated by free electron laser radiation.The influence of plasma inhomogeneities on the scattering spectrum is investigated by comparing density and temperature averaged scattering signals to calculations assuming homogeneous targets. We found discrepancies larger than 10% between the mean electron density and the effective density as well as between the mean temperature and the effective temperature.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑