7th International Conference on Matter and Radiation at Extremes (ICMRE2024)

X-ray spectroscopy is a powerful and widely used technique for diagnosing the internal conditions of laser-produced plasmas, which plays a key role in the study of high energy density physics. However, it is usually very challenging to extract reliable and accurate physical information from the measured x-ray spectra, especially for the integrated spectra coming from a range of plasma conditions. Here we present a complex spatiotemporally resolved analysis of time- and space-integrated x-ray emission spectroscopy from relativistic laser plasmas. Particle-in-cell (PIC) simulations using the PICLS code are performed to investigate the laser-solid interaction within a picosecond (ps). The subsequent plasma evolution is simulated with the hydrodynamic code FLASH on a larger timescale (hundreds of ps). With the outputs from PIC and hydrodynamic simulations, atomic kinetics-spectroscopy simulations by FLYCHK [1], SCFLY [2], and ATOMIC [3] codes are used to generate a series of synthetic spectra. A full-time evolution of electron temperature, density, and ionization state of laser-produced plasmas is thus extracted and then verified by the comparison between the measured and synthetic spectra. It demonstrates that the combination of x-ray spectroscopy, atomic physics, and multi-scale simulations is a promising method to characterize the dynamic evolution of plasmas created by short-pulse lasers, and is also an effective benchmark for numerical simulations.

x-ray spectroscopy,laser-solid interaction,dense plasma