Inference of the electron temperature in ICF implosions from X-ray spectra*

Two main approaches to assessing the electron temperature in ICF implosions are now being considered, which are based on measuring, respectively, line emission from a high-Z dopant such as krypton [1] or spectral continuum of 15 to 30 keV from electrons scattering off the D and T ions [2,3]. However, both types of the X-ray emission are due to suprathermal free electrons, which likely deviate from Maxwellian. We present the first theoretical study of both the line and continuum X-ray spectra from the hot-spot accounting for this deviation. In particular, we show that inferring the electron temperature as if the emitting electrons are Maxwellian gives a lower value than the actual one [4].

References

[1] H. Chen et al. Phys. Plasmas 24 (2017) 072715

[2] L. Jarrott, et al. Rev. Sci. Inst. 87 (2016) 11E534

[3] D. B. Thorn et al. Proc. SPIE 10390 (2017) 1039009

[4] G. Kagan et al. https://arxiv.org/abs/1710.01343