Cascaded ion emissions from copper plasma produced by an X-ray free-electron laser

T. Burian; J. Krása; M. Šmíd; M. Krupka; M. Stránský; Z. Jurek; R. Santra; J. Chalupský; L. Vyšín; A. Horynová; J. Bulička; Š. Jelínek; M. Kozlová; M. Mašek; O. Humphries; C. Baehtz; V. Bouffetier; E. Brambrink; V. Cerantola; T. E. Cowan; V. Hájková; J. Kaa; Z. Konôpková; M. Makita; X. Pan; T. R. Preston; J.-P. Schwinkendorf; A. Schropp; R. Štefaníková; W. Wang; U. Zastrau; K. Falk; L. Juha

doi:10.1063/5.0314214

Volume 11 Issue 5

Sep. 2026

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Article Navigation > Matter and Radiation at Extremes > 2026 > 11(5): 057601

T. Burian, J. Krása, M. Šmíd, M. Krupka, M. Stránský, Z. Jurek, R. Santra, J. Chalupský, L. Vyšín, A. Horynová, J. Bulička, Š. Jelínek, M. Kozlová, M. Mašek, O. Humphries, C. Baehtz, V. Bouffetier, E. Brambrink, V. Cerantola, T. E. Cowan, V. Hájková, J. Kaa, Z. Konôpková, M. Makita, X. Pan, T. R. Preston, J.-P. Schwinkendorf, A. Schropp, R. Štefaníková, W. Wang, U. Zastrau, K. Falk, L. Juha. Cascaded ion emissions from copper plasma produced by an X-ray free-electron laser[J]. Matter and Radiation at Extremes, 2026, 11(5): 057601. doi: 10.1063/5.0314214

Citation:

T. Burian, J. Krása, M. Šmíd, M. Krupka, M. Stránský, Z. Jurek, R. Santra, J. Chalupský, L. Vyšín, A. Horynová, J. Bulička, Š. Jelínek, M. Kozlová, M. Mašek, O. Humphries, C. Baehtz, V. Bouffetier, E. Brambrink, V. Cerantola, T. E. Cowan, V. Hájková, J. Kaa, Z. Konôpková, M. Makita, X. Pan, T. R. Preston, J.-P. Schwinkendorf, A. Schropp, R. Štefaníková, W. Wang, U. Zastrau, K. Falk, L. Juha. Cascaded ion emissions from copper plasma produced by an X-ray free-electron laser[J]. Matter and Radiation at Extremes, 2026, 11(5): 057601. doi: 10.1063/5.0314214

Citation:

T. Burian, J. Krása, M. Šmíd, M. Krupka, M. Stránský, Z. Jurek, R. Santra, J. Chalupský, L. Vyšín, A. Horynová, J. Bulička, Š. Jelínek, M. Kozlová, M. Mašek, O. Humphries, C. Baehtz, V. Bouffetier, E. Brambrink, V. Cerantola, T. E. Cowan, V. Hájková, J. Kaa, Z. Konôpková, M. Makita, X. Pan, T. R. Preston, J.-P. Schwinkendorf, A. Schropp, R. Štefaníková, W. Wang, U. Zastrau, K. Falk, L. Juha. Cascaded ion emissions from copper plasma produced by an X-ray free-electron laser[J]. Matter and Radiation at Extremes, 2026, 11(5): 057601. doi: 10.1063/5.0314214

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Cascaded ion emissions from copper plasma produced by an X-ray free-electron laser

doi: 10.1063/5.0314214

T. Burian^1
,,
J. Krása^{1
,
,
,},
M. Šmíd^2
,,
M. Krupka^{1, 3
,},
M. Stránský^1
,,
Z. Jurek^4
,,
R. Santra^{4, 5
,},
J. Chalupský^1
,,
L. Vyšín^1
,,
A. Horynová^{1, 6
,},
J. Bulička^{1, 7
,},
Š. Jelínek^{1, 3, 7
,},
M. Kozlová^{3, 8
,},
M. Mašek^1
,,
O. Humphries^9
,,
C. Baehtz^{2, 9
,},
V. Bouffetier^2
,,
E. Brambrink^9
,,
V. Cerantola^{10
,},
T. E. Cowan^2
,,
V. Hájková^1
,,
J. Kaa^{11
,},
Z. Konôpková^9
,,
M. Makita^9
,,
X. Pan^2
,,
T. R. Preston^9
,,
J.-P. Schwinkendorf^2
,,
A. Schropp^{12
,},
R. Štefaníková^{2, 13
,},
W. Wang^{9, 12
,},
U. Zastrau^9
,,
K. Falk^{1, 2
,},
L. Juha^1
,

1.
Department of Radiation and Chemical Physics, Institute of Physics, Czech Academy of Sciences, Na Slovance 2, 18200 Prague 8, Czech Republic
2.
Institute of Radiation Physics, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Bautzner Landstraße 400, 01328 Dresden, Germany
3.
Laser Plasma Department, Institute of Plasma Physics, Czech Academy of Sciences, Za Slovankou 3, 18200 Prague 8, Czech Republic
4.
Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
5.
Department of Physics, University of Hamburg, Notkestraße 9-11, 22607 Hamburg, Germany
6.
Department of Nuclear Chemistry, Faculty of Nuclear Science and Physical Engineering, Czech Technical University in Prague, Břehová 7, 11519 Prague 1, Czech Republic
7.
Department of Surface and Plasma Science, Faculty of Mathematics and Physics, Charles University, V Holešovičkách 2, 18200 Prague 8, Czech Republic
8.
The Extreme Light Infrastructure ERIC, ELI Beamlines Facility, Za Radnicí 835, 25241 Dolní Břežany, Czech Republic
9.
European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
10.
Department of Earth and Environmental Sciences, University of Milano-Bicocca, Piazza dell’Ateneo Nuovo 1, 20126 Milan, Italy
11.
Carl Zeiss SMT GmbH, Rudolf-Eber-Straße 2, 73447 Oberkochen, Germany
12.
Centre for X-Ray and Nano Science CXNS, Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
13.
TUD Dresden University of Technology, 01062 Dresden, Germany

More Information

Corresponding author: a)Author to whom correspondence should be addressed: krasa@fzu.cz
Received Date: 2025-11-27
Accepted Date: 2026-05-05

Available Online: 2026-09-28

Publish Date: 2026-09-01

Abstract

Abstract

Ultrafast, high-power lasers operating in the near-infrared (NIR) region are key to accelerating ions to extremely high energies. By changing the laser wavelength from the NIR region to the hard X-ray range, the photon energy increases more than 10 000 times. The interaction mechanisms and, consequently, radiation attenuation lengths differ significantly between these two spectral ranges. Here we report the use of an X-ray free-electron laser (European XFEL, Germany) delivering 9.3 keV photons in 25 fs pulses and a total energy of 0.35 mJ on a solid target. Electrons and ions escaping from an irradiated 3 μm Cu foil into vacuum were investigated by a time-of-flight technique using windowless electron multipliers that enable the measurement of very weak currents. A model based on a shifted Maxwell–Boltzmann velocity distribution of species was used to analyze the detector signals. The method used made it possible to determine the temperatures of hot electrons and protons, their center-of-mass energy, the charge states of the isotopes ⁶³Cu and ⁶⁵Cu, and the magnitude of the voltage arising in the double layer that accelerated them, and to estimate the repetition frequency of their cascade emission from the plasma. Computer simulations revealed the evolution of the electron density and temperature, the ion charge state distribution, and the time scales of processes occurring in the bulk of irradiated matter. Good correlation of theoretical and experimental results over the range of high-energy-density states demonstrates the capability to provide critical data to develop plasma models in the warm dense matter regime.

The authors have no conflicts to disclose.
Conflict of Interest
Author Contributions
T. Burian: Conceptualization (equal); Investigation (equal); Methodology (equal); Resources (equal); Supervision (equal); Validation (equal). J. Krása: Conceptualization (equal); Formal analysis (equal); Methodology (equal); Resources (equal); Writing – original draft (equal). M. Šmíd: Data curation (equal); Investigation (equal); Project administration (equal); Supervision (equal); Writing – review & editing (equal). M. Krupka: Data curation (equal); Formal analysis (equal); Investigation (equal). M. Stránský: Data curation (equal); Formal analysis (equal). Z. Jurek: Data curation (equal); Formal analysis (equal); Writing – review & editing (equal). R. Santra: Data curation (equal); Formal analysis (equal); Writing – review & editing (equal). J. Chalupský: Data curation (equal); Formal analysis (equal); Investigation (equal); Writing – review & editing (equal). L. Vyšín: Data curation (equal); Investigation (equal). A. Horynová: Data curation (equal); Investigation (equal). J. Bulička: Data curation (equal); Investigation (equal). Š. Jelínek: Data curation (equal); Formal analysis (equal); Investigation (equal). M. Kozlová: Data curation (equal); Investigation (equal). M. Mašek: Data curation (equal); Formal analysis (equal). O. Humphries: Data curation (equal); Investigation (equal); Writing – review & editing (equal). C. Baehtz: Data curation (equal); Investigation (equal). V. Bouffetier: Data curation (equal); Investigation (equal). E. Brambrink: Data curation (equal); Investigation (equal). V. Cerantola: Data curation (equal); Investigation (equal). T. E. Cowan: Project administration (equal); Resources (equal); Supervision (equal). V. Hájková: Data curation (equal); Formal analysis (equal); Investigation (equal). J. Kaa: Data curation (equal); Investigation (equal). Z. Konôpková: Data curation (equal); Investigation (equal). M. Makita: Data curation (equal); Investigation (equal). X. Pan: Data curation (equal); Investigation (equal). T. R. Preston: Data curation (equal); Investigation (equal). J.-P. Schwinkendorf: Data curation (equal); Investigation (equal). A. Schropp: Data curation (equal); Investigation (equal). R. Štefaníková: Data curation (equal); Investigation (equal). W. Wang: Data curation (equal); Investigation (equal). U. Zastrau: Data curation (equal); Investigation (equal). K. Falk: Conceptualization (equal); Methodology (equal); Project administration (equal). L. Juha: Conceptualization (equal); Funding acquisition (equal); Investigation (equal); Methodology (equal); Project administration (equal); Resources (equal); Supervision (equal); Writing – review & editing (equal).
The data that support the findings of this study are openly available upon reasonable request at https://in.xfel.eu/metadata/doi/10.22003/XFEL.EU-DATA-002806-00.

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References(48)

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