Application of Boltzmann kinetic equations to model X-ray-created warm dense matter and plasma

0584064 - ÚFP 2024 RIV GB eng J - Journal Article
Ziaja, B. - Bekx, J.J. - Mašek, M. - Medvedev, Nikita - Lipp, V. - Saxena, V. - Stránský, M.
Application of Boltzmann kinetic equations to model X-ray-created warm dense matter and plasma.
Philosophical Transactions of the Royal Society A-Mathematical Physical and Engineering Sciences. Roč. 381, č. 2253 (2023), č. článku 20220216. ISSN 1364-503X. E-ISSN 1471-2962
Grant - others:European Cooperation in Science and Technology(BE) CA17126
Program: COST
Institutional support: RVO:61389021
Keywords : Boltzmann kinetic equations * plasma * warm dense matter * X-ray free-electron lasers
OECD category: Fluids and plasma physics (including surface physics)
Impact factor: 5, year: 2022
Method of publishing: Limited access
https://royalsocietypublishing.org/doi/epdf/10.1098/rsta.2022.0216

In this review, we describe the application of Boltzmann kinetic equations for modelling warm dense matter and plasma formed after irradiation of solid materials with intense femtosecond X-ray pulses. Classical Boltzmann kinetic equations are derived from the reduced N-particle Liouville equations. They include only single-particle densities of ions and free electrons present in the sample. The first version of the Boltzmann kinetic equation solver was completed in 2006. It could model non-equilibrium evolution of X-ray-irradiated finite-size atomic systems. In 2016, the code was adapted to study plasma created from X-ray-irradiated materials. Additional extension of the code was then also performed, enabling simulations in the hard X-ray irradiation regime. In order to avoid treatment of a very high number of active atomic configurations involved in the excitation and relaxation of X-ray-irradiated materials, an approach called 'predominant excitation and relaxation path' (PERP) was introduced. It limited the number of active atomic configurations by following the sample evolution only along most PERPs. The performance of the Boltzmann code is illustrated in the examples of X-ray-heated solid carbon and gold. Actual model limitations and further model developments are discussed. This article is part of the theme issue 'Dynamic and transient processes in warm dense matter'.
Permanent Link: https://hdl.handle.net/11104/0352071