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Optical probing of ultrafast laser-induced solid-to-overdense-plasma transitions

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Light(Science & Applications) 2024年第5期13卷 973-984页

作者： Yasmina Azamoum Georg Alexander Becker Sebastian Keppler Guillaume Duchateau Stefan Skupin Mickael Grech Fabrice Catoire Sebastian Hell Issa Tamer Marco Hornung Marco Hellwing Alexander Kessler Franck Schorcht Malte Christoph Kaluza GSI Helmholtzzentrum für Schwerionenforschung Planckstr.164291 DarmstadtGermany. Helmholtz institute Jena Fröbelstieg 307743 JenaGermany. institute of Optics and Quantum Electronics Friedrich-SchillerUniversität JenaMax-Wien-Platz 107743 JenaGermany. CEA-CESTA 15 Avenue des SablièresCS6000133116 Le BarpCedexFrance institut Lumière Matière UMR 5306-CNRSUniversitéde Lyon 169622 VilleurbanneFrance. LULI CNRSCEASorbonne UniversitéInstitut Polytechnique de ParisPalaiseauFrance. Universitéde bordeaux-CNRS-CEA CELIAUMR 5107 TalenceFrance

Understanding the solid target dynamics resulting from the interaction with an ultrashort laser pulse is a challenging fundamental multi-physics problem involving atomic and solid-state physics,plasma physics,and laser *** of the initial interplay of the underlying processes is essential to many applications ranging from lowpower laser regimes like laser-induced ablation to high-power laser regimes like laser-driven ion *** the properties of the so-called pre-plasma formed as the laser pulse’s rising edge ionizes the target is complicated from the theoretical and experimental point of view,and many aspects of this laser-induced transition from solid to overdense plasma over picosecond timescales are still open *** the one hand,laser-driven ion acceleration requires precise control of the pre-plasma because the efficiency of the acceleration process crucially depends on the target properties at the arrival of the relativistic intensity peak of the *** the other hand,efficient laser ablation requires,for example,preventing the so-called“plasma shielding”.By capturing the dynamics of the initial stage of the interaction,we report on a detailed visualization of the pre-plasma formation and ***-thin diamond-like carbon foils are shown to transition from solid to plasma during the laser rising edge with intensitiesdence sub-picosecond dynamics of an expanding plasma with densities above 10^(23)cm^(−3)(about 100 times the critical plasma density).The complementarity of a solid-state interaction model and kinetic plasma description provides deep insight into the interplay of initial ionization,collisions,and expansion.

关键词： laser acceleration solid

Collisionless shock acceleration of protons in a plasma slab produced in a gas jet by the collision of two laser-driven hydrodynamic shockwaves

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Matter and Radiation at Extremes 2024年第2期9卷 12-25页

作者： J.-R.Marquès L.Lancia P.Loiseau P.Forestier-Colleoni M.Tarisien E.Atukpor V.Bagnoud C.Brabetz F.Consoli J.Domange F.Hannachi P.Nicolaï M.Salvadori B.Zielbauer LULI CNRSÉcole PolytechniqueCEASorbonne UniversitéInstitut Polytechnique de Paris91128 Palaiseau CedexFrance CEA DAMDIF91297 Arpajon CedexFrance UniversitéParis-Saclay CEALMCE91680 Bruyères-le-ChatelFrance CENBG CNRS-IN2P3Universitéde Bordeaux33175 Gradignan CedexFrance GSI Helmholtzzentrum für Schwerionenforschung GmbH Planckstraße 164291 DarmstadtGermany University of Darmstadt Schloßgartenstr.764289 DarmstadtGermany ENEA Fusion and Technologies for Nuclear Safety department C.R.FrascatiVia Enrico Fermi 45FrascatiRomeItaly CELIA Universitéde Bordeaux–CNRS–CEA33405 TalenceFrance UniversitéParis-Saclay CEALIDYL91191 Gif-sur-YvetteFrance

We have recently proposed a new technique of plasma tailoring by laser-driven hydrodynamic shockwaves generated on both sides of a gas jet[Marquès et al.,*** 28,023103(2021)].In a continuation of this numerical work,we study experimentally the influence of the tailoring on proton acceleration driven by a high-intensity picosecond laser in three cases:without tailoring,by tailoring only the entrance side of the picosecond laser,and by tailoring both sides of the gas *** tailoring,the acceleration is transverse to the laser axis,with a low-energy exponential spectrum,produced by Coulomb *** the front side of the gas jet is tailored,a forward acceleration appears,which is significantly enhanced when both the front and back sides of the plasma are *** forward acceleration produces higher-energy protons,with a peaked spectrum,and is in good agreement with the mechanism of collisionless shock acceleration(CSA).The spatiotemporal evolution of the plasma profile is characterized by optical shadowgraphy of a probe *** refraction and absorption of this beam are simulated by post-processing 3D hydrodynamic simulations of the plasma *** with the experimental results allows estimation of the thickness and near-critical density of the plasma slab produced by tailoring both sides of the gas *** parameters are in good agreement with those required for CSA.

关键词： acceleration hydrodynamic collision

Multi-dimensional Simulation of Phase Change by a 0D-2D Model Coupling via Stefan Condition

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Communications on Applied mathematics and Computation 2023年第2期5卷 853-884页

作者： Adrien Drouillet Romain Le Tellier Raphaël Loubère mathieu Peybernes Louis Viot institut de mathématiques de bordeaux Universitéde Bordeaux33405 Talence CedexFrance CEA-deS-IRESNE-DTN CEA Cadarache13108 Saint Paul-lez-DuranceFrance

Considering phase changes associated with a high-temperature molten material cooled down from the outside,this work presents an improvement of the modelling and the numerical simulation of such processes for an application pertaining to the safety of light water nuclear *** a core meltdown accident,the behaviour of the core melt(aka corium)into a steel vessel is of tremendous importance when evaluating the vessel *** correctly the heat fluxes requires the numerical simulation of the interaction between the liquid material and its solid counterpart which forms during the solidification process,but also may melt *** simulate this configuration,encoun-tered in various industrial applications,one considers a bi-phase model constituted by a liquid phase in contact and interaction with its solid *** liquid phase may solidify in presence of low energetic source,while the solid phase may melt due to an intense heat flux from the high-temperature *** the frame of the in-house legacy code,several simplifying assumptions(0D multi-layer discretization,instantaneous heat transfer via a quadratic temperature profile in solids)are made for the modelling of such phase *** the present work,these shortcomings are illustrated and further overcome by solving a 2D heat conduction model in the solid by a mixed Raviart-Thomas finite element method coupled to the liquid phase due to heat and mass exchanges through Stefan *** liquid phase is modeled with a 0D multi-layer *** 0D-liquid and 2D-solid mod-els are coupled by a Stefan like phase change interface *** sanity checks are performed to assess the validity of the approach on 1D and 2D academical configurations for which exact or reference solutions are *** more advanced situations(genu-ine multi-dimensional phase changes and an"industrial-like scenario")are simulated to verify the appropriate behavior of the obtained coupled simulation schem

关键词： Simulation of phase change Fusion Solidification 0D multi-layer model 2D heat conduction model Model coupling

A Posteriori Stabilized Sixth-Order Finite Volume Scheme with Adaptive Stencil Construction:Basics for the 1D Steady-State Hyperbolic Equations

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Communications on Applied mathematics and Computation 2023年第2期5卷 751-775页

作者： Gaspar J.Machado Stéphane Clain Raphaël Loubère Centre of Physics and department of mathematics University of MinhoCampus of Azurém4800-058 GuimaraesPortugal CNRS and institut de mathématiques de bordeaux(IMB) Universitéde BordeauxTalenceFrance

We propose an adaptive stencil construction for high-order accurate finite volume schemes a posteriori stabilized devoted to solve one-dimensional steady-state hyperbolic *** accuracy(up to the sixth-order presently)is achieved,thanks to polynomial recon-structions while stability is provided with an a posteriori MOOD method which controls the cell polynomial degree for eliminating non-physical oscillations in the vicinity of *** supplemented this scheme with a stencil construction allowing to reduce even further the numerical *** stencil is shifted away from troubles(shocks,discontinuities,etc.)leading to less oscillating polynomial *** on linear,Burgers',and Euler equations,we demonstrate that the adaptive stencil technique manages to retrieve smooth solutions with optimal order of accuracy but also irregular ones without spurious ***,we numerically show that the approach allows to reduce the dissipation still maintaining the essentially non-oscillatory behavior.

关键词： Finite volume MOOD Adaptive stencil Steady-state solution Euler equations High order

Optimizing laser coupling,matter heating,and particle acceleration from solids using multiplexed ultraintense lasers

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Matter and Radiation at Extremes 2024年第4期9卷 16-28页

作者： Weipeng Yao Motoaki Nakatsutsumi Sébastien Buffechoux Patrizio Antici Marco Borghesi Andrea Ciardi Sophia N.Chen Emmanuel d’Humières Laurent Gremillet Robert Heathcote Vojtech Horny Paul McKenna Mark N.Quinn Lorenzo Romagnani Ryan Royle Gianluca Sarri Yasuhiko Sentoku Hans-Peter Schlenvoigt Toma Toncian Olivier Tresca Laura Vassura Oswald Willi Julien Fuchs LULI-CNRS CEASorbonne UniversitéEcole PolytechniqueInstitut Polytechnique de ParisF-91128 Palaiseau CedexFrance Sorbonne Université Observatoire de ParisUniversité PSLCNRSLERMAF-75005 ParisFrance INRS-EMT 1650 BoulLionel-BouletVarennesQuebec J3X 1S2Canada Center for Plasma Physics School of Mathematics and PhysicsQueen’s University BelfastBelfast BT71NNUnited Kingdom “Horia Hulubei”National institute for Physics and Nuclear Engineering 30 Reactorului StreetRO-077125 Bucharest-MagureleRomania University of bordeaux Centre Lasers Intenses et ApplicationsCNRSCEAUMR 5107F-33405 TalenceFrance CEA DAMDIFF-91297 ArpajonFrance Université Paris-Saclay CEALMCE91680 Bruyères-le-ChatelFrance Central Laser Facility STFC Rutherford Appleton LaboratoryDidcotUnited Kingdom SUPA Department of PhysicsUniversity of StrathclydeGlasgow G40NGUnited Kingdom department of Physics University of NevadaRenoNevada 89557USA institute of Laser Engineering Osaka University2-6 YamadaokaSuitaOsaka 565-0871Japan institut fur Laser und Plasmaphysik Heinrich Heine Universitat DusseldorfDusseldorfGermany

Realizing the full potential of ultrahigh-intensity lasers for particle and radiation generation will require multi-beam arrangements due to technology ***,we investigate how to optimize their coupling with solid ***,we show that overlapping two intense lasers in a mirror-like configuration onto a solid with a large preplasma can greatly improve the generation of hot electrons at the target front and ion acceleration at the target *** underlying mechanisms are analyzed through multidimensional particle-in-cell simulations,revealing that the self-induced magnetic fields driven by the two laser beams at the target front are susceptible to reconnection,which is one possible mechanism to boost electron *** addition,the resistive magnetic field generated during the transport of the hot electrons in the target bulk tends to improve their *** simulations also indicate that such effects can be further enhanced by overlapping more than two laser beams.

关键词： laser acceleration particle

Dynamics of a rigid body in a two-dimensional incompressible perfect fluid and the zero-radius limit dedicated to Professor Jean-Yves Chemin on the Occasion of His 60th Birthday

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Science China mathematics 2019年第6期62卷 1205-1218页

作者： Franck Sueur institut de mathématiques de bordeaux CNRS UMR 5251 Université de Bordeaux

In this survey we report some recent results on the dynamics of a rigid body immersed in a twodimensional incompressible perfect fluid, with an emphasis on the zero-radius limit.

关键词： fluid-structure interaction point vortex perfect incompressible fluid

INVARIANCE AND STABILITY OF THE PROFILE EQUATIONS OF GEOMETRIC OPTICS

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Acta mathematica Scientia 2011年第6期31卷 2141-2158页

作者： Guy Mtivier Jeffrey Rauch institut de mathmatiques de bordeaux Universit de Bordeaux department of mathematics University of Michigan

The profile equations of geometric optics are described in a form invariant under the natural transformations of first order systems of partial differential equations. This allows us to prove that various strategies for computing profile equations are equivalent. We prove that if L generates an evolution on L2 the same is true of the profile equations. We prove that the characteristic polynomial of the profile equations is the localization of the characteristic polynomial of the background operator at （y, dφ（y）） where φ is the background phase. We prove that the propagation cones of the profile equations are subsets of the propagation cones of the background operator.

关键词： geometric optics profile equation localisation vector bundles propagation cones

A FAST FREE MEMORY METHOD FOR AN EFFICIENT COMPUTATION OF CONVOLUTION KERNELS

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Journal of Computational mathematics 2023年第6期41卷 1093-1116页

作者： Matthieu Aussal Marc Bakry Ecole Polytechnique(CMAP) INRIAInstitut Polytechnique ParisRoute de Saclay 91128PalaiseauFrance

We introduce the Fast Free Memory method(FFM),a new implementation of the Fast Multipole Method(FMM)for the evaluation of convolution *** FFM aims at being easier to implement while maintaining a high level of performance,capable of handling industrially-sized *** FFM avoids the implementation of a recursive tree and is a kernel independent *** give the algorithm and the relevant complexity *** quasi-linear complexity enables the evaluation of convolution products with up to one billion *** illustrate numerically the capacities of the FFM by solving Boundary Integral Equations problems featuring dozen of millions of *** implementation is made freely available under the GPL 3.0 license within the Gypsilab framework.

关键词： Convolution product Fast multipole method Boundary integral equations Open-source

Numerical Approximation of a Compressible Multiphase System

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Communications in Computational Physics 2014年第5期15卷 1237-1265页

作者： Remi Abgrall Harish Kumar inria and institut de mathématiques de bordeaux Institut Polytechnique de Bordeaux200 route de la Vieille Tour33405 TalenceFrance. department of mathematics IIT DelhiNew DelhiIndia-110016.

The numerical simulation of non conservative system is a difficult challenge for two reasons at *** first one is that it is not possible to derive jump relations directly from conservation principles,so that in general,if the model description is non ambiguous for smooth solutions,this is no longer the case for discontinuous *** the numerical view point,this leads to the following situation:if a scheme is stable,its limit for mesh convergence will depend on its dissipative *** is well known since at least[1].In this paper we are interested in the“dual”problem:given a system in non conservative form and consistent jump relations,how can we construct a numerical scheme that will,for mesh convergence,provide limit solutions that are the exact solution of the *** order to investigate this problem,we consider a multiphase flow model for which jump relations are *** scheme is an hybridation of Glimm scheme and Roe scheme.

关键词： Non conservative systems numerical approximation Glimm’s scheme Roe’s scheme.