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9Complex Systems of Charged Particles and their Interactions with Electromagnetic Radiation 2019
ULTRA-RELATIVISTIC FE PLASMA WITH GJ/CM3 ENERGY DENSITY CREATED BY FEMTOSECOND LASER PULSES
M.A. Alkhimova1, A.Ya. Faenov1,2, T.A. Pikuz1,2, I.Yu. Skobelev1,3, S. A. Pikuz1,3 M. Nishiuchi4, H. Sakaki4, A. S. Pirozhkov4, A. Sagisaka4, N.P. Dover4, Ko. Kondo4, K. Ogura4, Y. Fukuda4, H. Kiriyama4, M. Kando4, R. Kodama2,5, K. Kondo4
Joint Institute for High Temperatures of the Russian Academy of Sciences, Moscow, Russia, e-mail:
[email protected] 2Institute of Open and Transdisciplinary Research Initiatives, Osaka University, Osaka, Japan National Research Nuclear University «MEPhI», Moscow, Russia 4Kansai Photon Science Institute(KPSI), National Institutes for Quantum and Radiological Science
and Technology(QST), Kizugawa, Kyoto, Japan 5Institute of Laser Engineering, Osaka University, Osaka, Japan
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Plasma formed by femtosecond laser pulses with ultra-relativistic intensities (Ilaser >10 W/cm2)
on thin solid-state foils is of great interest since such plasma is an effective source of ultra-bright X-ray and gamma radiation, beams of high-energy ions, electrons and neutrons. Just X-ray radiation diagnostic allows to provide the monitoring of plasma source parameters since it strongly depends on experimental conditions [1]. This work we focused on studying features of X-ray
emission from stainless steel plasma generated by femtosecond laser pulses when its intensity on
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target surface reached ultra-relativistic value Iiaser ~ 5 xio W/cm at high laser contrast level ~ 1012. We report about x-ray spectroscopic measurements that were provided at recent experiments at J-KAREN-P laser facility [2] and following plasma parameters determination. The spectrometer with high spatial resolution equipped by spherically bent alpha-quartz crystal was implemented to measure X-ray emission from the front side of steel foil target at the wavelength range X = 1.7 - 2.1 A. To determine main plasma parameters, we provided kinetic calculations of multi-charged ions emission spectra using collisional-radiative computational code PrismSpect [3]. Making following comparison of measured x-ray spectra and corresponding kinetic modeling, we found that solid density (N ~
8*1022 cm-3) iron plasma with high electron temperature up to Te ~ 2.5 keV could be generated at
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such experimental conditions. We also demonstrated that at laser intensity on target of 5 x 10 W/cm2 (in
average, with fluctuation of 30% (a)) the matters state with ultra-high energy density
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~ 0.8 x 10 J/cm reached in the laser target interaction region. References
[1] M.A. Alkhimova et al. 2017 Optics Express 25 (23) 29501-29511.
[2] H.Kiriyama et al. 2018 Optics letters 43 (11) 2595-2598 .
[3] Prism Computational Sciences, software tools for scientific research and commercial applications in the physical sciences and engineering, http://www.prism-cs.com
