A new approach to target development for laboratory astrophysics experiments at high-power laser facilities is presented.With the dawn of high-power lasers,laboratory astrophysics has emerged as a field,bringing insig...A new approach to target development for laboratory astrophysics experiments at high-power laser facilities is presented.With the dawn of high-power lasers,laboratory astrophysics has emerged as a field,bringing insight into physical processes in astrophysical objects,such as the formation of stars.An important factor for success in these experiments is targetry.To date,targets have mainly relied on expensive and challenging microfabrication methods.The design presented incorporates replaceable machined parts that assemble into a structure that defines the experimental geometry.This can make targets cheaper and faster to manufacture,while maintaining robustness and reproducibility.The platform is intended for experiments on plasma flows,but it is flexible and may be adapted to the constraints of other experimental setups.Examples of targets used in experimental campaigns are shown,including a design for insertion in a high magnetic field coil.Experimental results are included,demonstrating the performance of the targets.展开更多
In this paper, the recent studies of laboratory astrophysics with strong magnetic fields in China have been reviewed.On the Shenguang-II laser facility of the National Laboratory on High-Power Lasers and Physics, a la...In this paper, the recent studies of laboratory astrophysics with strong magnetic fields in China have been reviewed.On the Shenguang-II laser facility of the National Laboratory on High-Power Lasers and Physics, a laser-driven strong magnetic field up to 200 T has been achieved. The experiment was performed to model the interaction of solar wind with dayside magnetosphere. Also the low beta plasma magnetic reconnection(MR) has been studied. Theoretically, the model has been developed to deal with the atomic structures and processes in strong magnetic field. Also the study of shock wave generation in the magnetized counter-streaming plasmas is introduced.展开更多
ELI-Beamlines(ELI-BL),one of the three pillars of the Extreme Light Infrastructure endeavour,will be in a unique position to perform research in high-energy-density-physics(HEDP),plasma physics and ultra-high intensit...ELI-Beamlines(ELI-BL),one of the three pillars of the Extreme Light Infrastructure endeavour,will be in a unique position to perform research in high-energy-density-physics(HEDP),plasma physics and ultra-high intensity(UHI)ð>10^(22) W=cm^(2)) lasereplasma interaction.Recently the need for HED laboratory physics was identified and the P3(plasma physics platform)installation under construction in ELI-BL will be an answer.The ELI-BL 10 PW laser makes possible fundamental research topics from high-field physics to new extreme states of matter such as radiation-dominated ones,high-pressure quantum ones,warm dense matter(WDM)and ultra-relativistic plasmas.HEDP is of fundamental importance for research in the field of laboratory astrophysics and inertial confinement fusion(ICF).Reaching such extreme states of matter now and in the future will depend on the use of plasma optics for amplifying and focusing laser pulses.This article will present the relevant technological infrastructure being built in ELI-BL for HEDP and UHI,and gives a brief overview of some research under way in the field of UHI,laboratory astrophysics,ICF,WDM,and plasma optics.展开更多
The jets driven by magnetic reconnection in laser-plasma interactions are investi- gated experimentally. The diagnostics in the optical and X-ray ranges provide detailed information about the jet characteristics. The ...The jets driven by magnetic reconnection in laser-plasma interactions are investi- gated experimentally. The diagnostics in the optical and X-ray ranges provide detailed information about the jet characteristics. The plasma jets perpendicular to and along the target surface are observed clearly, which is evident signatures of laser driven magnetic reconnection. The jet formation is also investigated for different experimental parameters.展开更多
A new target design is presented to model high-energy radiative accretion shocks in polars. In this paper, we present the experimental results obtained on the GEKKO XII laser facility for the POLAR project. The experi...A new target design is presented to model high-energy radiative accretion shocks in polars. In this paper, we present the experimental results obtained on the GEKKO XII laser facility for the POLAR project. The experimental results are compared with 2 D FCI2 simulations to characterize the dynamics and the structure of plasma flow before and after the collision. The good agreement between simulations and experimental data confirms the formation of a reverse shock where cooling losses start modifying the post-shock region. With the multi-material structure of the target,a hydrodynamic collimation is exhibited and a radiative structure coupled with the reverse shock is highlighted in both experimental data and simulations. The flexibility of the laser energy produced on GEKKO XII allowed us to produce high-velocity flows and study new and interesting radiation hydrodynamic regimes between those obtained on the LULI2000 and Orion laser facilities.展开更多
The study of structure, thermodynamic state, equation of state(EOS) and transport properties of warm dense matter(WDM) has become one of the key aspects of laboratory astrophysics. This field has demonstrated its impo...The study of structure, thermodynamic state, equation of state(EOS) and transport properties of warm dense matter(WDM) has become one of the key aspects of laboratory astrophysics. This field has demonstrated its importance not only concerning the internal structure of planets, but also other astrophysical bodies such as brown dwarfs, crusts of old stars or white dwarf stars. There has been a rapid increase in interest and activity in this field over the last two decades owing to many technological advances including not only the commissioning of high energy optical laser systems, zpinches and X-ray free electron lasers, but also short-pulse laser facilities capable of generation of novel particle and X-ray sources. Many new diagnostic methods have been developed recently to study WDM in its full complexity. Even ultrafast nonequilibrium dynamics has been accessed for the first time thanks to subpicosecond laser pulses achieved at new facilities. Recent years saw a number of major discoveries with direct implications to astrophysics such as the formation of diamond at pressures relevant to interiors of frozen giant planets like Neptune, metallic hydrogen under conditions such as those found inside Jupiter’s dynamo or formation of lonsdaleite crystals under extreme pressures during asteroid impacts on celestial bodies. This paper provides a broad review of the most recent experimental work carried out in this field with a special focus on the methods used. All typical schemes used to produce WDM are discussed in detail. Most of the diagnostic techniques recently established to probe WDM are also described. This paper also provides an overview of the most prominent examples of these methods used in experiments. Even though the main emphasis of the publication is experimental work focused on laboratory astrophysics primarily at laser facilities, a brief outline of other methods such as dynamic compression with z-pinches and static compression using diamond anvil cells(DAC) is also included. Some relevant theoretical and computational efforts related to WDM and astrophysics are mentioned in this review.展开更多
We have developed a new radiography setup with a short-pulse laser-driven x-ray source. Using a radiography axis perpendicular to both long- and short-pulse lasers allowed optimizing the incident angle of the short-pu...We have developed a new radiography setup with a short-pulse laser-driven x-ray source. Using a radiography axis perpendicular to both long- and short-pulse lasers allowed optimizing the incident angle of the short-pulse laser on the x-ray source target. The setup has been tested with various x-ray source target materials and different laser wavelengths.Signal to noise ratios are presented as well as achieved spatial resolutions. The high quality of our technique is illustrated on a plasma flow radiograph obtained during a laboratory astrophysics experiment on POLARs.展开更多
We report on the design and first results from experiments looking at the formation of radiative shocks on the ShenguangII(SG-II)laser at the Shanghai Institute of Optics and Fine Mechanics in China.Laser-heating of a...We report on the design and first results from experiments looking at the formation of radiative shocks on the ShenguangII(SG-II)laser at the Shanghai Institute of Optics and Fine Mechanics in China.Laser-heating of a two-layer CH/CH–Br foil drives a∼40 km/s shock inside a gas cell filled with argon at an initial pressure of 1 bar.The use of gas-cell targets with large(several millimetres)lateral and axial extent allows the shock to propagate freely without any wall interactions,and permits a large field of view to image single and colliding counter-propagating shocks with time-resolved,pointprojection X-ray backlighting(∼20µm source size,4.3 keV photon energy).Single shocks were imaged up to 100 ns after the onset of the laser drive,allowing to probe the growth of spatial nonuniformities in the shock apex.These results are compared with experiments looking at counter-propagating shocks,showing a symmetric drive that leads to a collision and stagnation from∼40 ns onward.We present a preliminary comparison with numerical simulations with the radiation hydrodynamics code ARWEN,which provides expected plasma parameters for the design of future experiments in this facility.展开更多
In this paper, we present a reanalysis of the silicon He-α X-ray spectrum emission in Fujioka et al.’s 2009 photoionization experiment. The computations were performed with our radiative-collisional code, RCF. The c...In this paper, we present a reanalysis of the silicon He-α X-ray spectrum emission in Fujioka et al.’s 2009 photoionization experiment. The computations were performed with our radiative-collisional code, RCF. The central ingredients of our computations are accurate atomic data, inclusion of satellite lines from doubly excited states and accounting for the reabsorption of the emitted photons on their way to the spectrometer. With all these elements included, the simulated spectrum turns out to be in good agreement with the experimental spectrum.展开更多
A developing application of laser-driven currents is the generation of magnetic fields of picosecond-nanosecond duration with magnitudes exceeding B=10 T.Single-loop and helical coil targets can direct laser-driven di...A developing application of laser-driven currents is the generation of magnetic fields of picosecond-nanosecond duration with magnitudes exceeding B=10 T.Single-loop and helical coil targets can direct laser-driven discharge currents along wires to generate spatially uniform,quasi-static magnetic fields on the millimetre scale.Here,we present proton deflectometry across two axes of a single-loop coil ranging from 1 to 2 mm in diameter.Comparison with proton tracking simulations shows that measured magnetic fields are the result of kiloampere currents in the coil and electric charges distributed around the coil target.Using this dual-axis platform for proton deflectometry,robust measurements can be made of the evolution of magnetic fields in a capacitor coil target.展开更多
Magnetic reconnection driven by laser plasma interactions attracts great interests in the recent decades. Motivated by the rapid development of the laser technology, the ultra strong magnetic field generated by the la...Magnetic reconnection driven by laser plasma interactions attracts great interests in the recent decades. Motivated by the rapid development of the laser technology, the ultra strong magnetic field generated by the laser-plasma accelerated electrons provides unique environment to investigate the relativistic magnetic field annihilation and reconnection. It opens a new way for understanding relativistic regimes of fast magnetic field dissipation particularly in space plasmas,where the large scale magnetic field energy is converted to the energy of the nonthermal charged particles. Here we review the recent results in relativistic magnetic reconnection based on the laser and collisionless plasma interactions.The basic mechanism and the theoretical model are discussed. Several proposed experimental setups for relativistic reconnection research are presented.展开更多
基金Additional funding was provided by the Student Grant Competition of CTU(No.SGS22/180/OHK4/3T/14)the Ministry of Education,Youth&Sports of the Czech Republic(No.LM2018114)+1 种基金the Horizon 2020 project Laserlab-Europe V(No.871124)This work was funded by the Helmholtz Association(No.VHNG-1338).
文摘A new approach to target development for laboratory astrophysics experiments at high-power laser facilities is presented.With the dawn of high-power lasers,laboratory astrophysics has emerged as a field,bringing insight into physical processes in astrophysical objects,such as the formation of stars.An important factor for success in these experiments is targetry.To date,targets have mainly relied on expensive and challenging microfabrication methods.The design presented incorporates replaceable machined parts that assemble into a structure that defines the experimental geometry.This can make targets cheaper and faster to manufacture,while maintaining robustness and reproducibility.The platform is intended for experiments on plasma flows,but it is flexible and may be adapted to the constraints of other experimental setups.Examples of targets used in experimental campaigns are shown,including a design for insertion in a high magnetic field coil.Experimental results are included,demonstrating the performance of the targets.
基金supported by National Basic Research Program of China (973 Program) under grant No.2013CBA01503the National Natural Science Foundation of China under grant No.11573040, 11503041 and 11135012supported by the Science Challenge Program
文摘In this paper, the recent studies of laboratory astrophysics with strong magnetic fields in China have been reviewed.On the Shenguang-II laser facility of the National Laboratory on High-Power Lasers and Physics, a laser-driven strong magnetic field up to 200 T has been achieved. The experiment was performed to model the interaction of solar wind with dayside magnetosphere. Also the low beta plasma magnetic reconnection(MR) has been studied. Theoretically, the model has been developed to deal with the atomic structures and processes in strong magnetic field. Also the study of shock wave generation in the magnetized counter-streaming plasmas is introduced.
基金The authors acknowledge support from the project ELI:Extreme Light Infrastructure from European Regional Devel-opment(CZ.02.1.01/0.0/0.0/15-008/0000162)Also supported by the project High Field Initiative(CZ.02.1.01/0.0/0.0/15-003/0000449)from European Regional Development Fund.
文摘ELI-Beamlines(ELI-BL),one of the three pillars of the Extreme Light Infrastructure endeavour,will be in a unique position to perform research in high-energy-density-physics(HEDP),plasma physics and ultra-high intensity(UHI)ð>10^(22) W=cm^(2)) lasereplasma interaction.Recently the need for HED laboratory physics was identified and the P3(plasma physics platform)installation under construction in ELI-BL will be an answer.The ELI-BL 10 PW laser makes possible fundamental research topics from high-field physics to new extreme states of matter such as radiation-dominated ones,high-pressure quantum ones,warm dense matter(WDM)and ultra-relativistic plasmas.HEDP is of fundamental importance for research in the field of laboratory astrophysics and inertial confinement fusion(ICF).Reaching such extreme states of matter now and in the future will depend on the use of plasma optics for amplifying and focusing laser pulses.This article will present the relevant technological infrastructure being built in ELI-BL for HEDP and UHI,and gives a brief overview of some research under way in the field of UHI,laboratory astrophysics,ICF,WDM,and plasma optics.
基金supported by National Natural Science Foundation of China (Nos.10925421,10734130,10735050)National Basic Research Program of China (973 Program) (No.2007CB815103)
文摘The jets driven by magnetic reconnection in laser-plasma interactions are investi- gated experimentally. The diagnostics in the optical and X-ray ranges provide detailed information about the jet characteristics. The plasma jets perpendicular to and along the target surface are observed clearly, which is evident signatures of laser driven magnetic reconnection. The jet formation is also investigated for different experimental parameters.
基金supported by the‘Programme National de Physique Stellaire’(PNPS)of CNRS/INSU,Francesupported by ANR Blanc grant No.12-BS09-025-01 SILAMPALABEX Plas@Par grant No.11-IDEX-0004-02 from theFrench agency ANR
文摘A new target design is presented to model high-energy radiative accretion shocks in polars. In this paper, we present the experimental results obtained on the GEKKO XII laser facility for the POLAR project. The experimental results are compared with 2 D FCI2 simulations to characterize the dynamics and the structure of plasma flow before and after the collision. The good agreement between simulations and experimental data confirms the formation of a reverse shock where cooling losses start modifying the post-shock region. With the multi-material structure of the target,a hydrodynamic collimation is exhibited and a radiative structure coupled with the reverse shock is highlighted in both experimental data and simulations. The flexibility of the laser energy produced on GEKKO XII allowed us to produce high-velocity flows and study new and interesting radiation hydrodynamic regimes between those obtained on the LULI2000 and Orion laser facilities.
基金supported by the Helmholtz Association under VH-NG1338
文摘The study of structure, thermodynamic state, equation of state(EOS) and transport properties of warm dense matter(WDM) has become one of the key aspects of laboratory astrophysics. This field has demonstrated its importance not only concerning the internal structure of planets, but also other astrophysical bodies such as brown dwarfs, crusts of old stars or white dwarf stars. There has been a rapid increase in interest and activity in this field over the last two decades owing to many technological advances including not only the commissioning of high energy optical laser systems, zpinches and X-ray free electron lasers, but also short-pulse laser facilities capable of generation of novel particle and X-ray sources. Many new diagnostic methods have been developed recently to study WDM in its full complexity. Even ultrafast nonequilibrium dynamics has been accessed for the first time thanks to subpicosecond laser pulses achieved at new facilities. Recent years saw a number of major discoveries with direct implications to astrophysics such as the formation of diamond at pressures relevant to interiors of frozen giant planets like Neptune, metallic hydrogen under conditions such as those found inside Jupiter’s dynamo or formation of lonsdaleite crystals under extreme pressures during asteroid impacts on celestial bodies. This paper provides a broad review of the most recent experimental work carried out in this field with a special focus on the methods used. All typical schemes used to produce WDM are discussed in detail. Most of the diagnostic techniques recently established to probe WDM are also described. This paper also provides an overview of the most prominent examples of these methods used in experiments. Even though the main emphasis of the publication is experimental work focused on laboratory astrophysics primarily at laser facilities, a brief outline of other methods such as dynamic compression with z-pinches and static compression using diamond anvil cells(DAC) is also included. Some relevant theoretical and computational efforts related to WDM and astrophysics are mentioned in this review.
基金the support of RFBR grant 14-29-06099Competitiveness Programme of NRNU MEPhI
文摘We have developed a new radiography setup with a short-pulse laser-driven x-ray source. Using a radiography axis perpendicular to both long- and short-pulse lasers allowed optimizing the incident angle of the short-pulse laser on the x-ray source target. The setup has been tested with various x-ray source target materials and different laser wavelengths.Signal to noise ratios are presented as well as achieved spatial resolutions. The high quality of our technique is illustrated on a plasma flow radiograph obtained during a laboratory astrophysics experiment on POLARs.
基金the Royal Society(UK)through a University Research Fellowship(URF-R-180032)a Research Fellows Enhancement Award(RGF-EA-180240)+2 种基金an International Exchanges grant(IES-R3-170140)a Research Grant(RG2017-R2)The authors would like to thank the operation group of the SG-II laser facility.C.S.acknowledges support from the French INSU-PNPS programme.U.C.acknowledges support by the project Advanced Research(CZ.02.1.01/0.0/0.0/16_019/0000789)from European Regional Development Fund(ADONIS)。
文摘We report on the design and first results from experiments looking at the formation of radiative shocks on the ShenguangII(SG-II)laser at the Shanghai Institute of Optics and Fine Mechanics in China.Laser-heating of a two-layer CH/CH–Br foil drives a∼40 km/s shock inside a gas cell filled with argon at an initial pressure of 1 bar.The use of gas-cell targets with large(several millimetres)lateral and axial extent allows the shock to propagate freely without any wall interactions,and permits a large field of view to image single and colliding counter-propagating shocks with time-resolved,pointprojection X-ray backlighting(∼20µm source size,4.3 keV photon energy).Single shocks were imaged up to 100 ns after the onset of the laser drive,allowing to probe the growth of spatial nonuniformities in the shock apex.These results are compared with experiments looking at counter-propagating shocks,showing a symmetric drive that leads to a collision and stagnation from∼40 ns onward.We present a preliminary comparison with numerical simulations with the radiation hydrodynamics code ARWEN,which provides expected plasma parameters for the design of future experiments in this facility.
基金supported by the Science Challenge Project(No.TZ2016005)the National Natural Science Foundation of China(Nos.11903006,12073043 and U1930108)the Strategic Priority Research Program of Chinese Academy of Sciences(No.XDA25030700)。
文摘In this paper, we present a reanalysis of the silicon He-α X-ray spectrum emission in Fujioka et al.’s 2009 photoionization experiment. The computations were performed with our radiative-collisional code, RCF. The central ingredients of our computations are accurate atomic data, inclusion of satellite lines from doubly excited states and accounting for the reabsorption of the emitted photons on their way to the spectrometer. With all these elements included, the simulated spectrum turns out to be in good agreement with the experimental spectrum.
基金This paper was supported by the LLNL Academic Partnership in ICF,EPSRC grants EP/L01663X/1 and EP/L000644/1the Czech Republic MSMT targeted support of Large Infrastructures+1 种基金ELI Beamlines Project LQ1606 of the National Programme of Sustainability IIThe contribution of the JIHT RAS team was completed within the framework of the Russian Ministry state assignment for Science and Higher Education(topic#01201357846).
文摘A developing application of laser-driven currents is the generation of magnetic fields of picosecond-nanosecond duration with magnitudes exceeding B=10 T.Single-loop and helical coil targets can direct laser-driven discharge currents along wires to generate spatially uniform,quasi-static magnetic fields on the millimetre scale.Here,we present proton deflectometry across two axes of a single-loop coil ranging from 1 to 2 mm in diameter.Comparison with proton tracking simulations shows that measured magnetic fields are the result of kiloampere currents in the coil and electric charges distributed around the coil target.Using this dual-axis platform for proton deflectometry,robust measurements can be made of the evolution of magnetic fields in a capacitor coil target.
基金supported by the project High Field Initiative(CZ.02.1.01/0.0/0.0/15003/0000449)from European Regional Development Fundby AFOSR(Grant No.FA9550-17-1-0382)。
文摘Magnetic reconnection driven by laser plasma interactions attracts great interests in the recent decades. Motivated by the rapid development of the laser technology, the ultra strong magnetic field generated by the laser-plasma accelerated electrons provides unique environment to investigate the relativistic magnetic field annihilation and reconnection. It opens a new way for understanding relativistic regimes of fast magnetic field dissipation particularly in space plasmas,where the large scale magnetic field energy is converted to the energy of the nonthermal charged particles. Here we review the recent results in relativistic magnetic reconnection based on the laser and collisionless plasma interactions.The basic mechanism and the theoretical model are discussed. Several proposed experimental setups for relativistic reconnection research are presented.