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147 results on '"Nejdl, Jaroslav"'

1. Compact laser-driven plasma X-ray source for time-resolved diffraction, spectroscopy, and imaging experiments at ELI Beamlines

Author

Pulnova, Yelyzaveta, Parkman, Tomáš, Angelov, Borislav, Baranova, Iulia, Zymaková, Ana, Cipiccia, Silvia, Fardin, Luca, Yorke, Briony A., Antipenkov, Roman, Peceli, Davorin, Hort, Ondřej, Mai, Dong-Du, Andreasson, Jakob, and Nejdl, Jaroslav

Subjects
Physics - Optics
Abstract

Experimentally measured characteristics of a kHz laser-driven Cu plasma X-ray source that was recently commissioned at ELI Beamlines facility are reported. The source can be driven either by an in-house developed high contrast sub-20 fs near-infrared TW laser based on optical parametric chirped-pulse amplification technology, or by a more conventional Ti:sapphire laser delivering 12 mJ, 45 fs pulses. The X-ray source parameters obtained with the two driving lasers are compared. Measured photon flux of the order up to 10^{12} K{\alpha} photons/4{\pi}/s is reported. Furthermore, experimental platforms for ultrafast X-ray diffraction and X-ray absorption and/or emission spectroscopy based on the reported source are described.

Published
2024

2. Monochromatic high-harmonic generation by Bessel-Gauss beam in periodically modulated media

Author

Finke, Ondřej, Vábek, Jan, Dvořáček, Matěj, Jurkovičová, Lucie, Albrecht, Martin, Ovcharenko, Hrehorij, Hort, Ondřej, and Nejdl, Jaroslav

Subjects
Physics - Optics
Abstract

High harmonic generation (HHG) has become a multipurpose source of coherent XUV radiation used in various applications. One of the notable aspects of HHG is its wide spectrum consisting of many harmonic orders. This might represent a bottleneck in HHG utility for applications requiring a single wavelength. We propose a method to generate radiation consisting of a single high-order harmonic frequency employing Bessel-Gauss driving beam and a periodically modulated gaseous medium. We validate it by analytical calculations and numerical simulations. Our method provides a way to generate monochromatic harmonic radiation directly from the source without the need for additional monochromatizing optics. Thus, it represents a substantial enhancement of the flux and simplification of the setup for numerous applications requiring monochromatic short-wavelength radiation.

Published
2024
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3. Bright coherent attosecond X-ray pulses from beam-driven relativistic mirrors

Author

Lamač, Marcel, Valenta, Petr, Nejdl, Jaroslav, Chaulagain, Uddhab, Jeong, Tae Moon, and Bulanov, Sergei Vladimirovich

Subjects
Physics - Plasma Physics, Physics - Optics
Abstract

Bright ultrashort X-ray pulses allow scientists to observe ultrafast motion of atoms and molecules. Coherent light sources, such as the X-ray free electron laser (XFEL), enable remarkable discoveries in cell biology, protein crystallography, chemistry or materials science. However, in contrast to optical lasers, lack of X-ray mirrors demands XFELs to amplify radiation over a single pass, requiring tens or hundreds of meters long undulators to produce bright femtosecond X-ray pulses. Here, we propose a new ultrafast coherent light source based on laser reflection from a relativistic mirror driven by a relativistic charged particle beam in micrometer-scale plasma. We show that reflection of millijoule-level laser pulses from such mirrors can produce bright, coherent and bandwidth-tunable attosecond X-ray pulses with peak intensity and spectral brightness comparable to XFELs. In addition, we find that beam-driven relativistic mirrors are highly robust, with laser-induced damage threshold exceeding solid-state components by at least two orders of magnitude. Our results promise a new way for bright coherent attosecond X-ray pulse generation, suitable for unique applications in fundamental physics, biology and chemistry.

Published
2024

5. Single-shot spatial coherence of a plasma based soft X-ray laser

Author

Albrecht, Martin, Hort, Ondřej, Kozlová, Michaela, Krůs, Miroslav, and Nejdl, Jaroslav

Subjects
Physics - Optics
Abstract

Many applications of short-wavelength radiation impose strong requirements on the coherence properties of the source. However, the measurement of such properties poses a challenge, mainly due to the lack of high-quality optics and source fluctuations that often violate assumptions necessary for multi-shot or cumulative techniques. In this article, we present a new method of single-shot spatial coherence measurement adapted to the soft X-ray spectral range. Our method is based on a far-field diffraction pattern from a binary transmission mask consisting of a non-redundant array of simple apertures. Unlike all currently available methods, our technique allows measuring radiation field with an arbitrary spatial coherence function without any prior assumption on intensity distribution or the model of the degree of spatial coherence. We experimentally verified the technique by retrieving the spatial coherence functions of individual shots of laser-driven Zn plasma soft X-ray laser with one- and two-dimensional masks. The experimental results revealed nontrivial illumination pattern and strong asymmetry of the spatial coherence function, which clearly calls for abandoning the often used models that assume rotational invariance of the coherence function, such as the popular Gaussian-Schell beam model.

Published
2023

6. Anomalous Relativistic Emission from Self-Modulated Plasma Mirrors

Author

Lamač, Marcel, Mima, Kunioki, Nejdl, Jaroslav, Chaulagain, Uddhab, and Bulanov, Sergey Vladimirovich

Subjects
Physics - Plasma Physics, Physics - Optics
Abstract

The interaction of intense laser pulses with plasma mirrors has demonstrated the ability to generate high-order harmonics, producing a bright source of extreme ultraviolet (XUV) radiation and attosecond pulses. Here, we report an unexpected transition in this process. We show that the loss of spatio-temporal coherence in the reflected high-harmonics can lead to a new regime of highly-efficient coherent XUV generation, with an extraordinary property where the radiation is directionally anomalous, propagating parallel to the mirror surface. With analytical calculations and numerical particle-in-cell simulations, we discover that the radiation emission is due to laser-driven oscillations of relativistic electron nanobunches which originate from a plasma surface instability induced by collisionless absorption of the laser., Comment: 6 pages, 3 figures

Published
2023

7. Bright continuously-tunable VUV source for ultrafast spectroscopy

Author

Jurkovičová, Lucie, Ltaief, Ltaief Ben, Roos, Andreas Hult, Hort, Ondřej, Finke, Ondřej, Albrecht, Martin, Hoque, Ziaul, Klimešová, Eva, Sundaralingam, Akgash, Antipenkov, Roman, Grenfell, Annika, Špaček, Alexandr, Szuba, Wojciech, Krikunova, Maria, Mudrich, Marcel, Nejdl, Jaroslav, and Andreasson, Jakob

Subjects
Physics - Atomic Physics, Physics - Atomic and Molecular Clusters, Physics - Optics
Abstract

Ultrafast electron dynamics drive phenomena such as photochemical reactions, catalysis, and light harvesting. To capture such dynamics in real-time, femtosecond to attosecond light sources are extensively used. However, an exact match between the excitation photon energy and a characteristic resonance is crucial. High-harmonic generation sources are exceptional in terms of pulse duration but limited in spectral tunability in the VUV range. Here, we present a monochromatic femtosecond source continuously tunable around 21 eV photon energy utilizing the second harmonic of an OPCPA laser system to drive high-harmonic generation. The unique tunability of the source is verified in an experiment probing the interatomic Coulombic decay in doped He nanodroplets across the He absorption bands. Moreover, we achieved intensities sufficient for driving non-linear processes using a tight focusing of the VUV beam. We demonstrated it on the observation of collective autoionization of multiply excited pure He nanodroplets., Comment: 12 pages, 5 figures, submitted to Nat. Commun

Published
2023
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8. A Multipurpose End-Station for Atomic, Molecular and Optical Sciences and Coherent Diffractive Imaging at ELI Beamlines

Author

Klimešová, Eva, Kulyk, Olena, Hoque, Ziaul, Roos, Andreas Hult, Khakurel, Krishna P., Rebarz, Mateusz, Jurkovič, Matej, Albrecht, Martin, Finke, Ondřej, Lera, Roberto, Hort, Ondřej, Mai, Dong-Du, Nejdl, Jaroslav, Sokol, Martin, Fink, Rasmus Burlund, Ltaief, Ltaief Ben, Westphal, Daniel, Wolf, Adam, Laštovička, Tomáš, Frassetto, Fabio, Poletto, Luca, Andreasson, Jakob, and Krikunova, Maria

Subjects
Physics - Instrumentation and Detectors
Abstract

We report on the status of a users' end-station, MAC: a Multipurpose station for Atomic, molecular and optical sciences and Coherent diffractive imaging, designed for studies of structure and dynamics of matter in the femtosecond time-domain. MAC is located in the E1 experimental hall on the high harmonic generation (HHG) beamline of the ELI Beamlines facility. The extreme ultraviolet beam from the HHG beamline can be used at the MAC end-station together with a synchronized pump beam (which will cover the NIR/Vis/UV or THz range) for time-resolved experiments on different samples. Sample delivery systems at the MAC end-station include a molecular beam, a source for pure or doped clusters, ultrathin cylindrical or flat liquid jets, and focused beams of substrate-free nanoparticles produced by an electrospray or a gas dynamic virtual nozzle combined with an aerodynamic lens stack. We further present the available detectors: electron/ion time-of-flight and velocity map imaging spectrometers and an X-ray camera, and discuss future upgrades: a magnetic bottle electron spectrometer, production of doped nanodroplets and the planned developments of beam capabilities at the MAC end-station., Comment: 14 pages, 13 figures. This is a preprint of an article published in The European Physical Journal Special Topics, 2021

Published
2021
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10. Photoelectric charge from metallic filters: An online XUV pulse energy diagnostics.

Author

Staněk, Matyáš, Hort, Ondřej, Jurkovičová, Lucie, Albrecht, Martin, Finke, Ondřej, Nagyillés, Balázs, Farkas, Balázs, Csizmadia, Tamás, Grósz, Tímea, Körmöczi, Andor, Divéki, Zsolt, and Nejdl, Jaroslav

Subjects
ATOMIC physics, X-ray lasers, HIGHPASS electric filters, HARMONIC generation, RADIATION sources
Abstract

Extreme ultraviolet (XUV) radiation is a tool of choice for studying ultrafast processes and atomic physics. Most experiments employing sources of XUV radiation, such as high harmonic generation (HHG) or x-ray lasers, benefit from knowing the number of photons delivered to target in every single shot, because of the possible shot-to-shot pulse fluctuation of the sources. Nonetheless, many setups lack noninvasive XUV pulse energy diagnostics, hindering the simultaneous measurement of pulse energy and utilization of the XUV beam for applications. We present an online XUV pulse energy monitoring method based on the detection of photoelectric charge from thin metallic foil filters transmitting the XUV beam, which can be easily implemented at every pulsed XUV source that includes a high-pass filter system in the form of metallic filters. Consequently, implementation of our method is as straightforward as connecting the filter to an oscilloscope. In the paper, we describe all the physics aspects of such measurement and show the dependence of measured photoelectric charge on the incident pulse energy. To prove the versatility of our approach, we performed this measurement on two different high-flux HHG beamlines, taking consecutive shots at 1 kHz. [ABSTRACT FROM AUTHOR]

Published
2024
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13. Diagnostics for precise target positioning in ~10^22 W/cm2 laser-plasma experiments

Author

Vishnyakov, Evgeny, primary, Sagisaka, Akito, primary, Ogura, Koichi, primary, Pikuz, Tatiana, primary, Armstrong, C, primary, Pikuz, Sergey, primary, Gonzalez-Izquierdo, Bruno, primary, Esirkepov, Timur, primary, Yan, Wenchao, primary, Jeong, Tae Moon, primary, Singh, Sushil, primary, Hadjisolomou, Prokopis, primary, Finke, Ondřej, primary, Grittani, Gabriele Maria, primary, Nevrkla, Michal, primary, Lazzarini, Carlo Maria, primary, Velyhan, Andriy, primary, Hayakawa, Takehito, primary, Fukuda, Yuji, primary, Koga, James, primary, Ishino, Masahiko, primary, Kondo, Kotaro, primary, Miyasaka, Yasuhiro, primary, Kon, Akira, primary, Nishikino, Masaharu, primary, Nosach, Evgeny, primary, Khikhlukha, Danila, primary, Tsygvintsev, Ilia, primary, Kumar, Deepak, primary, Nejdl, Jaroslav, primary, Margarone, Daniele, primary, Sasorov, Pavel, primary, Weber, Stefan, primary, kando, masaki, primary, Kiriyama, Hiromitsu, primary, Kato, Yoshiaki, primary, Korn, Georg, primary, Kondo, Kiminori, primary, Bulanov, Sergei, primary, Kawachi, Tetsuya, primary, and Pirozhkov, Alexander, primary

Published
2023
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14. Instruments for best target position determination in the high-intensity laser-solid interaction experiment

Author

Vishnyakov, Eugene A., primary, Sagisaka, Akito, additional, Ogura, Koichi, additional, Pikuz, Tatiana A., additional, Armstrong, Chris D., additional, Pikuz, Sergey A., additional, Gonzalez-Izquierdo, Bruno, additional, Esirkepov, Timur Z., additional, Yan, Wenchao, additional, Jeong, Tae Moon, additional, Singh, Sushil, additional, Hadjisolomou, Prokopis, additional, Finke, Ondrej, additional, Grittani, Gabriele Maria, additional, Nevrkla, Michal, additional, Lazzarini, Carlo Maria, additional, Velyhan, Andriy, additional, Hayakawa, Takehito, additional, Fukuda, Yuji, additional, Koga, James K., additional, Ishino, Masahiko, additional, Kondo, Kotaro, additional, Miyasaka, Yasuhiro, additional, Kon, Akira, additional, Nishikino, Masaharu, additional, Nosach, Evgeny V., additional, Khikhlukha, Danila, additional, Tsygvintsev, Ilya P., additional, Kumar, Deepak, additional, Nejdl, Jaroslav, additional, Margarone, Daniele, additional, Sasorov, Pavel V., additional, Kando, Masaki, additional, Kiriyama, Hiromitsu, additional, Korn, Georg, additional, Kondo, Kiminori, additional, Bulanov, Sergei V., additional, Kawachi, Tetsuya, additional, and Pirozhkov, Alexander S., additional

Published
2023
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16. Multiscale modeling of HHG and its applications

Author

Vábek, Jan, primary, Finke, Ondrej, additional, Veyrinas, Kevin, additional, Valentin, Constance, additional, Němec, Tadeáš, additional, Descamps, Dominique, additional, Nevrkla, Michal, additional, Péjot, Clément, additional, Bobrova, Nadezda, additional, Burgy, Frédéric, additional, Jurkovičová, Lucie, additional, Albrecht, Martin, additional, Jancárek, Alexandr, additional, Constant, Eric, additional, Hort, Ondrej, additional, Mével, Eric, additional, Limpouch, Jiří, additional, Skupin, Stefan, additional, Nejdl, Jaroslav, additional, and Catoire, Fabrice, additional

Published
2023
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18. Multiscale modeling of HHG and its applications

Author

Vábek, Jan, Finke, Ondrej, Veyrinas, Kevin, Valentin, Constance, Němec, Tadeáš, Descamps, Dominique, Nevrkla, Michal, Péjot, Clément, Bobrova, Nadezda, Burgy, Frédéric, Jurkovič, M., Albrecht, Martin, Jancárek, Alexandr, Constant, Eric, Hort, Ondrej, Mével, Eric, Limpouch, Jiří, Skupin, Stefan, Nejdl, Jaroslav, Catoire, Fabrice, Centre d'Etudes Lasers Intenses et Applications (CELIA), Université de Bordeaux (UB)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Czech Technical University in Prague (CTU), ELI Beamlines, Institute of Physics of the Czech Academy of Sciences (FZU / CAS), Czech Academy of Sciences [Prague] (CAS)-Czech Academy of Sciences [Prague] (CAS), Institut Lumière Matière [Villeurbanne] (ILM), Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], optics-free focusing, [PHYS.PHYS.PHYS-ATOM-PH]Physics [physics]/Physics [physics]/Atomic Physics [physics.atom-ph], XUV focusing, [PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], electrical discharge, multi-scale HHG, quasi-phase matching, phase-matching, high harmonic generation
Abstract

Event: SPIE Optics + Optoelectronics, 2023, Prague, Czech Republic; High-harmonic generation (HHG) in gaseous media is a workhorse tool in attosecond science. Its description origins from the microscopic scale of a single atom or molecule interacting with a driving IR-laser pulse. However, its practical realization usually employs a macroscopic volume of the gas. The macroscopic aspect aggregates all the microscopic emitters and brings novel physical mechanisms that drive the generation. One of the key mechanisms within the macroscopic scale is the shaping of the driving pulse due to the non-linear response of the medium. We present a comprehensive numerical model describing and coupling the physics on both scales. The model consists of different modules that provide different levels of approximation to choose an optimal trade-off between accuracy and computational cost. We then use it to address two generation schemes, where we provide a detailed picture together with experimental realizations. The first scheme uses a long medium homogeneously pre-ionized by an electrical discharge to optimize the phase-matching of the harmonic signal. This scheme allows, in particular, for optimizing HHG in long media where the control is difficult because the driving pulse undergoes strong reshaping and defocusing due to the non-linear response after the entrance to the medium. The second scheme introduces a mechanism to control the divergence of the harmonic beam in thin targets. The divergence is driven by shaping the wavefront of the driving pulse. This allows for spectrally selective focusing of the harmonic beams without the use of optics, which leads to inevitable losses in the XUV region.

Published
2023
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19. Electron correlation dynamics in atomic Kr excited by XUV pulses and controlled by NIR laser pulses of variable intensity

Author

Roos, Andreas Hult, primary, Hoque, Ziaul, additional, Klimešová, Eva, additional, Ben Ltaief, Ltaief, additional, Medina, Cristian, additional, Jurkovič, Matej, additional, Albrecht, Martin, additional, Finke, Ondřej, additional, Hort, Ondřej, additional, Nejdl, Jaroslav, additional, Mudrich, Marcel, additional, Andreasson, Jakob, additional, and Krikunova, Maria, additional

Published
2023
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20. Instruments for best target position determination in the high-intensity laser-solid interaction experiment

Author

Menoni, Carmen S., Nejdl, Jaroslav, Vishnyakov, Eugene A., Sagisaka, Akito, Ogura, Koichi, Pikuz, Tatiana A., Armstrong, Chris, Pikuz, Sergey A., Gonzalez-Izquierdo, Bruno, Esirkepov, Timur Zh., Yan, Wenchao, Jeong, Tae Moon, Singh, Sushil, Hadjisolomou, Prokopis, Finke, Ondrej, Grittani, Gabriele Maria, Nevrkla, Michal, Lazzarini, Carlo Maria, Velyhan, Andriy, Hayakawa, Takehito, Fukuda, Yuji, Koga, James, Ishino, Masahiko, Kondo, Kotaro, Miyasaka, Yasuhiro, Kon, Akira, Nishikino, Masaharu, Nosach, Yevhen, Khiklukha, Danila, Tsygvintsev, Ilya, Kumar, Deepak, Nejdl, Jaroslav, Margarone, Daniele, Sasorov, Pavel V., Kando, Masaki, Kiriyama, Hiromitsu, Korn, Georg, Kondo, Kiminori, Bulanov, Sergei V., Kawachi, Tetsuya, and Pirozhkov, Alexander S.

Published
2023
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21. New probing techniques of radiative shocks

Author

Stehlé, Chantal, Kozlová, Michaela, Larour, Jean, Nejdl, Jaroslav, Champion, Norbert, Barroso, Patrice, Suzuki-Vidal, Francisco, Acef, Ouali, Delattre, Pierre-Alexandre, Dostál, Jan, Krus, Miroslav, and Chièze, Jean-Pierre

Published
2012
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22. Large area ion beam sputtered dielectric ultrafast mirrors for petawatt laser beamlines

Author

Willemsen, Thomas, primary, Chaulagain, Uddhab, additional, Havlíčková, Irena, additional, Borneis, Stefan, additional, Ebert, Wolfgang, additional, Ehlers, Henrik, additional, Gauch, Melanie, additional, Groß, Tobias, additional, Kramer, Daniel, additional, Laštovička, Tomáš, additional, Nejdl, Jaroslav, additional, Rus, Bedřich, additional, Schrader, Konrad, additional, Tolenis, Tomas, additional, Vaněk, František, additional, Velpula, Praveen K., additional, and Weber, Stefan, additional

Published
2022
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23. Laser-Driven Photon Sources and Exemplary Applications at ELI Beamlines

Author

Mai, Dong Du, primary, Pulnova, Yelyzaveta, additional, Espinoza, Shirly, additional, Klimešová, Eva, additional, Angelov, Borislav, additional, Hort, Ondrej, additional, Chaulagain, Uddhab, additional, Krikunova, Maria, additional, Molodozhentsev, Alexander, additional, Andreason, Jakob, additional, Nejdl, Jaroslav, additional, and Bulanov, Sergei, additional

Published
2022
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32. Update on laser-driven X-ray sources at ELI Beamlines

Author

Nejdl, Jaroslav, primary, Chaulagain, Uddhab, additional, Hort, Ondřej, additional, Mai, Du, additional, Albrecht, Martin, additional, Jurkovič, Matej, additional, Finke, Ondřej, additional, Karatodorov, Stefan, additional, Raclavský, Marek, additional, Lamač, Marcel, additional, Klimešová, Eva, additional, Hoque, Ziaul, additional, Hult Roos, Andreas, additional, Krikunova, Maria, additional, and Andreasson, Jakob, additional

Published
2021
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33. A multipurpose end-station for atomic, molecular and optical sciences and coherent diffractive imaging at ELI beamlines

Author

Klimešová, Eva, primary, Kulyk, Olena, additional, Hoque, Ziaul, additional, Roos, Andreas Hult, additional, Khakurel, Krishna P., additional, Rebarz, Mateusz, additional, Jurkovičová, Lucie, additional, Albrecht, Martin, additional, Finke, Ondřej, additional, Lera, Roberto, additional, Hort, Ondřej, additional, Mai, Dong-Du, additional, Nejdl, Jaroslav, additional, Sokol, Martin, additional, Fink, Rasmus Burlund, additional, Ben Ltaief, Ltaief, additional, Westphal, Daniel, additional, Wolf, Adam, additional, Laštovička, Tomáš, additional, Frassetto, Fabio, additional, Poletto, Luca, additional, Andreasson, Jakob, additional, and Krikunova, Maria, additional

Published
2021
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35. Characterization of the high harmonics source for the VUV ellipsometer at ELI Beamlines

Author

Espinoza, Shirly, primary, Samparisi, Fabio, additional, Frassetto, Fabio, additional, Richter, Steffen, additional, Rebarz, Mateusz, additional, Finke, Ondrej, additional, Albrecht, Martin, additional, Jurkovic, Matej, additional, Hort, Ondrej, additional, Fabris, Nicola, additional, Zymaková, Anna, additional, Mai, Dong Du, additional, Antipenkov, Roman, additional, Nejdl, Jaroslav, additional, Poletto, Luca, additional, and Andreasson, Jakob, additional

Published
2020
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36. Characterization of the high harmonics source for the VUV ellipsometer at ELI Beamlines

Author

Espinoza, Shirly, Samparisi, Fabio, Frassetto, Fabio, Richter, Steffen, Rebarz, Mateusz, Finke, Ondrej, Albrecht, Martin, Jurkovic, Matej, Hort, Ondrej, Fabris, Nicola, Zymaková, Anna, Mai, Dong Du, Antipenkov, Roman, Nejdl, Jaroslav, Poletto, Luca, Andreasson, Jakob, Espinoza, Shirly, Samparisi, Fabio, Frassetto, Fabio, Richter, Steffen, Rebarz, Mateusz, Finke, Ondrej, Albrecht, Martin, Jurkovic, Matej, Hort, Ondrej, Fabris, Nicola, Zymaková, Anna, Mai, Dong Du, Antipenkov, Roman, Nejdl, Jaroslav, Poletto, Luca, and Andreasson, Jakob

Abstract

In this paper, the authors present the characterization experiments of a 20 fs vacuum ultraviolet beam from a high harmonic generation source. The beam hits a silicon sample and passes a triple reflection gold polarizer located inside an ultrahigh vacuum chamber. The polarizer’s Malus curve was obtained; the total acquisition time for each point of the curve was 30 s. This aims to be the first vacuum ultraviolet time-resolved user station dedicated to ellipsometry. The high harmonic beam is generated by a 12 mJ, 1 kHz, 20 fs, in-house-developed laser and detected by a back-illuminated charge-coupled device.

Published
2020
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37. ELI Beamlines User Oriented High-Harmonic Beamline

Author

Hort, Ondřej, primary, Albrecht, Martin, additional, Finke, Ondřej, additional, Jurkovič, Matej, additional, Lera, Roberto, additional, Du Mai, D., additional, Klimešová, Eva, additional, Espinoza, Shirly, additional, Richter, Steffen, additional, Antipenkov, Roman, additional, Batysta, František, additional, Novák, Jakub, additional, Green, Jonathan T., additional, Andreasson, Jakob, additional, Krikunova, Maria, additional, and Nejdl, Jaroslav, additional

Published
2020
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38. XUV Reflection and Ellipsometry Experiments at ELIBeamlines

Author

Espinoza, Shirly, primary, Samparisi, Fabio, additional, Zahradník, Martin, additional, Albrecht, Martin, additional, Finke, Ondřej, additional, Antipenkov, Roman, additional, Hort, Ondřej, additional, Rebarz, Mateusz, additional, Jurkovič, Matej, additional, Poletto, Luca, additional, Nejdl, Jaroslav, additional, and Andreasson, Jakob, additional

Published
2020
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39. Progress on laser-driven x-ray sources at ELI Beamlines

Author

Nejdl, Jaroslav, primary, Mai, Dong-Du, additional, Chaulagain, Uddhab, additional, HOrt, Ondrej, additional, Finke, Ondrej, additional, Albrecht, Martin, additional, Jurkovic, Matej, additional, Lera, Roberto, additional, Karatodorov, Stefan, additional, Lamač, Marcel, additional, Vančura, Jakub, additional, Boháček, Karel, additional, Espinoza, Shirly J., additional, Richter, Steffen, additional, Rebarz, Mateusz, additional, Klimesova, Eva, additional, Krikunova, Maria, additional, Kolzová, Michaela, additional, Antipenkov, Roman, additional, Batysta, Frantisek, additional, Novák, Jakub, additional, Green, Jonathan T., additional, Andreasson, Jakob, additional, and Korn, Georg, additional

Published
2019
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41. X-ray phase contrast imaging of biological samples using a betatron X-ray source generated in a laser wakefield accelerator

Author

Chaulagain, U., Bohacek, K., Nejdl, Jaroslav, M., Krus, V., Horny, Mahieu, Benoît, Ta Phuoc, Kim, ELI Beamlines, Czech Technical University in Prague (CTU), Institute of Physics [Prague], Czech Academy of Sciences [Prague] (CAS), Laboratoire d'optique appliquée (LOA), École Nationale Supérieure de Techniques Avancées (ENSTA Paris)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), and Zaparucha, Pierre

Subjects
[PHYS.PHYS.PHYS-OPTICS] Physics [physics]/Physics [physics]/Optics [physics.optics], [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], [PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], [PHYS.PHYS.PHYS-PLASM-PH] Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2017

42. Progress on laser-driven X-ray sources at ELI Beamlines.

Author

Nejdl, Jaroslav, Dong-Du Mai, Chaulagain, Uddhab, Hort, Ondřej, Finke, Ondřej, Albrecht, Martin, Jurkovič, Matej, Lera, Roberto, Karatodorov, Stefan, Lamač, Marcel, Vančura, Jakub, Boháček, Karel, Espinoza, Shirly, Richter, Steffen, Rebarz, Mateusz, Klimešová, Eva, Krikunova, Maria, Kozlová, Michaela, Antipenkov, Roman, and Batysta, František

Published
2019
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44. Experimental study of counter propagating radiative shocks

Author

Singh, Raj Laxmi, Stehlé, Chantal, Suzuki-Vidal, Francisco, Kozlová, Michaela, Larour, Jean, Chaulagain, Uddhab, Clayson, Thomas, Nejdl, Jaroslav, Krus, Miroslav, Dostál, Jan, Dudzak, R., Barroso, Patrice, Acef, Ouali, Cotelo, M., Rodriguez, R., Gil, J. M., Laboratoire de Physique des Plasmas (LPP), Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École polytechnique (X)-Sorbonne Université (SU)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], Astrophysics::High Energy Astrophysical Phenomena, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

International audience; S 04 Atelier général PNPS Radiative shocks are present at different stages of stellar evolution, for instance in the stellar infancy when matter is accreted from the stellar disk to the photosphere of the young star and is also ejected in the form of stellar jets, up to the final stages as supernovae and the interaction of their remnants with the interstellar medium. Such shocks are strongly influenced by the radiation through its coupling with hydrodynamics. Thus their topology and dynamics are quite complex. Generating such hypersonic shocks in the laboratory, with controlled conditions, is thus an adequate tool to study the influence of radiation and to compare them with numerical simulations. So far, such laboratory astrophysics studies are performed on large-scale laser facilities, addressing hydrodynamic radiative shocks, in Xenon with very high velocity (50 - 150 km/s) and moderate pressure (0.1 - 1 bar). These experiments advance the understanding of the effect of radiation on the different shock components (radiative precursors, shock collapse, walls heating etc.). In continuation of these laboratory experiments, we recently performed experiments at PALS laser facility to study a fairly new topic focusing on the interaction of two counter propagating shocks. The objective is to understand the influence of one radiative precursor onto another, to achieve higher temperature in the compressed medium. In the astrophysical context, aforementioned studies are relevant for instance, collision of supernovae remnants and more indirectly the interaction of supernovae remnants with dense molecular clouds and the impact of accretion flows on a stellar atmosphere. The experiments have been able to launch shocks with different shock speeds (~30-55 km/s and 10-25 km/s), in varying gases (Ar, Xe) and pressures (~0.1-0.3 bar). Optical interferometry allowed us to estimate several physical parameters such as shock speed and electron density in the precursor, XUV spectroscopy allowed to give information about the shock temperature. We will present some preliminary results together with numerical simulations.

Published
2016

45. Experimental study of the collision of two laser-driven radiative shocks at the PALS laser

Author

Singh, Raj Laxmi, Stehlé, Chantal, Suzuki-Vidal, Francisco, Larour, Jean, Chaulagain, Uddhab, Clayson, Thomas, Nejdl, Jaroslav, Krus, Miroslav, Kozlová, Michaela, Dostál, Jan, Acef, Ouali, Barroso, Patrice, Cotelo, M., Velarde, P., Rodriguez Perez, R., Gil, J. M., Laboratoire de Physique des Plasmas (LPP), Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École polytechnique (X)-Sorbonne Université (SU)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph]
Abstract

International audience; Radiative shocks are present in various astrophysical contexts and can be proxy of fundamental accretion processes, for instance X-ray signatures from accretion shocks can be related to the rate of mass accretion onto forming stars. Thus the study of hypersonic shocks (Mach number >> 1) in the laboratory Under controlled conditions is of primary interest in order to study the influence of radiation, and to compare with numerical simulations. In the past decade, several experiments on radiative shocks have been performed on various large-scale laser facilities, demonstrating the formation of shocks in Xenon with velocities ~50 - 150 km/s in background gas pressures ~0.1 - 1 bar (Bouquet et al. 2004, Gonzalez et. al. 2006, Reighard et. al. 2007, Stehlé et al. 2010, Doss et al. 2011, Drake et al. 2011, Dizière et al. 2012, Stehlé et al. 2012, Chaulagain et al. 2015). Many advances have been achieved in understanding the effect of radiation on the different shock components (radiative precursor, shock collapse, wall heating etc.), however, these studies were focused solely on the case of a single radiative shock. We have recently conducted experiments at the PALS laser facility, looking at the collision between two counter streaming radiative shocks. Besides providing a new experimental platform, these experiments aimed at studying how one radiative precursor is influenced by the presence of another. The experiments launched shocks with different shock speeds (~30-55 km/s and 10-25 km/s), at a range of different pressures (~0.1-0.3 bar), and with different gases (Ar, Xe). Optical interferometry allowed us to estimate several physical parameters such as shock speed and electron density in the precursor, whereas the use of time and spatially resolved optical spectroscopy led to a number of spectral signatures. We will present preliminary results together with numerical simulations.

Published
2016

50. Radiative shocks at PALS: latest results and future prospects

Author

Stehlé, Chantal, Chaulagain, Uddhab, De Sà, Lionel, Ibgui, Laurent, Ciardi, Andrea, Larour, Jean, Kozlová, Michaela, Nejdl, Jaroslav, Suzuki-Vidal, Francisco, Barroso, Patrice, Velarde, P., Rodriguez Perez, R., Gil, J. M., Espinosa, G., Acef, Ouali, Laboratoire de Physique des Plasmas (LPP), Université Paris-Saclay-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-École polytechnique (X)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Institute of Physics [Prague], Czech Academy of Sciences [Prague] (CAS), Galaxies, Etoiles, Physique, Instrumentation (GEPI), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Instituto de Fusión Nuclear, Universidad Politécnica de Madrid (UPM), University of Coimbra, Dept Physic, University of Coimbra [Portugal] (UC), and Universidad Nacional Autónoma de México (UNAM)

Subjects
[PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph]
Abstract

International audience; affiche P53 Being able to produce and diagnose radiative shocks under controlled laboratory conditions is a key aspect to understand their role in astrophysical processes such as accretion in stellar formation. The ongoing study of radiative shocks using high-power lasers has significantly advanced our understanding on the physics of these complex flows. In particular, experiments at the Prague Asterix Laser System (PALS) have demonstrated the formation of radiative shocks in Xenon with a characteristic velocity of 50-60 km/s. Latest results on the generation on radiative shocks at PALS demonstrate the feasibility of fielding novel probing techniques such as time-resolved imaging using an X-ray laser at 21.2 nm, allowing to probe simultaneously the high-density shock-front together with the lower-density radiative precursor in front of the shock. These results will be compared with 2-D radiative-hydrodynamic simulations using the code ARWEN. Future experimental campaigns will focus on spectroscopic measurements of the different shock regions together with new experimental configurations such as the interaction of counter-streaming radiative shocks. These prospects will be presented and discussed from both experimental and simulation point of view. This work is supported by french ANR STARSHOCK (grant 08-BLAN-0263-07), Programme National de Physique Stellaire" (PNPS) of CNRS/INSU, France, Observatoire de Paris and labex Plas@Par ( ANR-11-IDEX-0004-02 )

Published
2014

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