Download or read book ETUDE DE L IONISATION LASER DE JETS DE GAZ HAUTE DENSITE written by REINHOLD.. BRUCKNER and published by . This book was released on 1994 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: LA PRODUCTION DE JETS DE GAZ HAUTE DENSITE COMME CIBLES GAZEUSES POUR DIVERSES APPLICATIONS (INTERACTION AVEC FAISCEAU DE PARTICULE OU IMPULSION LASER ULTRA INTENSE) EST ENTREPRISE. LE TRAVAIL EST AXE SUR LA CONCEPTION DES BUSES. UNE ETUDE THEORIQUE EST ACCOMPAGNEE D'UNE ETUDE EXPERIMENTALE. L'EXPERIENCE ANALYSE PLUSIEURS ASPECTS DES ECOULEMENTS: EVOLUTION TEMPORELLE, PROFIL DE DENSITE, FRONTS DE CHOC ETC. LES MOYENS DE DIAGNOSTICS COMPRENNENT L'INTERFEROMETRIE MACH-ZEHNDER, LA STRIOSCOPIE, LA DIFFUSION RAYLEIGH. LA PRODUCTION DE PLASMAS DANS UN JET DE GAZ A ETE EFFECTUEE PAR IMPULSION LASER NANOSECONDE. L'ANALYSE EXPERIMENTALE EST PHENOMENOLOGIQUE. LES DIAGNOSTICS SONT L'IMAGERIE RAPIDE, L'INTERFEROMETRIE ET L'OMBROSCOPIE. IL S'AVERE QU'UN PROFIL DE DENSITE MODIFIE FORTEMENT LE PROCESSUS DE LA FORMATION DU PLASMA. CELUI-CI EST PLUS VOLUMINEUX ET PLUS FORTEMENT IONISE QUE CELUI CREE DANS UN GAZ AMBIANT
Download or read book ETUDE EXPERIMENTALE DE L IONISATION OPTIQUE D UN JET D ARGON HAUTE PRESSION PAR UNE IMPULSION LASER FEMTOSECONDE INTENSE written by FREDERIC.. BLASCO and published by . This book was released on 1997 with total page 143 pages. Available in PDF, EPUB and Kindle. Book excerpt: LA PROPAGATION D'UNE IMPULSION LASER FEMTOSECONDE INTENSE, AU TRAVERS D'UN GAZ PERMET DE PRODUIRE, TRES RAPIDEMENT, UN PLASMA COMPOSE D'ELECTRONS ET D'IONS POSITIFS MULTICHARGES. L'IONISATION EST PRINCIPALEMENT LE RESULTAT DE L'INTERACTION ENTRE LES PHOTONS LASER ET LES ATOMES DE GAZ, ET SE PRODUIT PAR EFFET MULTIPHOTONIQUE OU PAR EFFET TUNNEL SUIVANT L'INTENSITE LASER MISE EN JEU. A DES INTENSITES DE L'ORDRE DE 10#1#6 W/CM#2 L'IONISATION D'UN GAZ, PRODUIT PAR UNE IMPULSION LASER FEMTOSECONDE INTENSE, CONDUIT A UNE DEFOCALISATION ET A UNE MODIFICATION DU SPECTRE DE CETTE IMPULSION AU COURS DE SA PROPAGATION. CECI RESULTE DE LA FORTE DYNAMIQUE D'IONISATION QUI PREND PLACE AU COURS DE LA MONTEE DE L'IMPULSION LASER. L'UTILISATION DE JETS SUPERSONIQUES PRESENTANT DE FORT GRADIENTS EN BORD NOUS A PERMIS DE MONTRER QUE LA DEFOCALISATION PEUT ETRE NOTABLEMENT REDUITE, PERMETTANT AINSI D'ATTEINDRE DES ETATS D'IONISATION IMPORTANTS. NOUS AVONS PAR AILLEURS CARACTERISE LE FRONT D'IONISATION PAR L'ETUDE DU DECALAGE D'UNE IMPULSION LASER SONDE TRANSMISE DANS LE PLASMA. CE DECALAGE SPECTRAL EST ASSOCIE A DEUX EFFETS : DYNAMIQUE D'IONISATION DU FRONT ET VARIATION RAPIDE DE L'INDICE DU A LA PROPAGATION DU FRONT A UNE VITESSE PROCHE DE LA VITESSE DE LA LUMIERE. NOUS AVONS MESURE POUR LA PREMIERE FOIS, LA DERIVE EN FREQUENCE D'UNE IMPULSION LASER ULTRA-COURTE PAR COLLISION AVEC UN FRONT D'IONISATION RELATIVISTE DANS DEUX DIRECTIONS ET NOUS AVONS MONTRE CLAIREMENT LA POSSIBILITE D'ACCELERER DES PHOTONS A L'AIDE D'UN FRONT D'IONISATION RELATIVISTE. POUR UNE IMPULSION D'INTENSITE EGALE OU SUPERIEURE A 10#1#8 W/CM#2 LES EFFETS RELATIVISTES ET NON LINEAIRES CONTRIBUENT A UNE AUTOFOCALISATION ET AUTOGUIDAGE DE L'IMPULSION LASER. POUR UNE INTENSITE DE L'ORDRE DE 5 10#1#8 W/CM#2 ON OBSERVE UNE FILAMENTATION DU FAISCEAU EN TROIS CANAUX. LES CONDITIONS D'OBTENTION DE L'AUTOFOCALISATION RELATIVISTE SONT TRES DEPENDANTES DES CONDITIONS DE FOCALISATION DANS LE JET.
Download or read book INTERACTION DE LASERS DE FORTE INTENSITE 10 1 5 10 1 8 W CM 2 AVEC UN GAZ OU UN JET DE GAZ POUR DIFFERENTES DUREES D IMPULSIONS written by ERIC.. DE WISPELAERE and published by . This book was released on 1997 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: CE TRAVAIL DE THESE EST UNE ETUDE EXPERIMENTALE, DANS LE CADRE DE L'ACCELERATION LASER DE PARTICULES, DES PROCESSUS RELATIFS A LA PROPAGATION D'IMPULSIONS COURTES EN PLASMAS SOUS DENSES. UNE PREMIERE PARTIE EST CONSACREE A LA MISE EN EVIDENCE DE LA REFRACTION DU LASER INDUITE PAR L'IONISATION DU GAZ. LES RESULTATS OBTENUS, COMME LES MODIFICATIONS SPECTRALES DE L'IMPULSION OU LA REFRACTION RESOLUE TEMPORELLEMENT, SONT COMPARES A CEUX D'UN CODE PARTICULAIRE 2D. LA REFLECTIVITE RAMAN RETRODIFFUSEE ISSUE DE L'INTERACTION LASER-PLASMA EN IMPULSION COURTE (120FS), EST MESUREE ET CALCULEE A L'AIDE D'UN MODELE ANALYTIQUE 1D. UN BON ACCORD EST OBTENU EN TENANT COMPTE DE LA REFRACTION ET DES EFFETS HYDRODYNAMIQUES. PAR AILLEURS, DES SIGNATURES D'ONDES PLASMA RAMAN FORTEMENT AMORTIES SUGGERENT QUE L'INSTABILITE DANS LE CAS DES IMPULSIONS 1,8 PS, TEND VERS LE REGIME COMPTON. LA SECONDE PARTIE DE LA THESE CONSTITUE UNE ETUDE DETAILLEE DE LA FORMATION D'UN CANAL DE PLASMA, OBTENU PAR FOCALISATION D'UNE IMPULSION DE 600 PS DANS UN JET DE GAZ. LA FORMATION DU CANAL EST CARACTERISEE PAR INTERFEROMETRIE ET PAR DIFFUSION THOMSON. LA DIFFERENCE DE DENSITE ENTRE LE CENTRE ET LE BORD DU CANAL EST MESUREE DANS NOS CONDITIONS A N#E=8.10#1#9 CM#-#3, CE QUI CORRESPOND A UNE VARIATION RELATIVE DE DENSITE D'UN FACTEUR 4. LA COMPARAISON AVEC UN CODE 1D CALCULANT L'EVOLUTION THERMIQUE ET HYDRODYNAMIQUE DU PLASMA, MONTRE UN BON ACCORD GENERAL, EN PARTICULIER CONCERNANT T#E(T) ET N#E(T). UNE CONCLUSION IMPORTANTE DE CETTE ETUDE EST LA POSSIBILITE D'AJUSTER LE RAYON ET LA DENSITE SUR AXE DU CANAL PAR LA VARIATION DE L'ENERGIE LASER ET DE LA PRESSION DE NEUTRE DU JET.
Download or read book Laser driven Ion Acceleration with High density Gas jet Targets and Application to Elemental Analysis written by Pilar Puyuelo Valdes and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this joint thesis, performed between the French Institute CENBG (Bordeaux) and the Canadian Institute INRS (Varennes), laser driven ion acceleration and an application of the beams are studied. The first part, carried out at CENBG and on the PICO2000 laser facility of the LULI laboratory, studies both experimentally and using numerical particle-in-cell (PIC) simulations, the interaction of a high power infrared laser with a high density gas target. The second part, performed at ALLS laser facility of the EMT-INRS institute, investigates the utilization of laser generated beams for elementary analysis of various materials and artifacts. In this work, firstly the characteristics of the two lasers, the experimental configurations, and the different employed particle diagnostics (Thomson parabolas, radiochromic films, etc.) employed are introduced.In the first part, a detailed study of the supersonic high density gas jets which have been used as targets at LULI is presented, from their conceptual design using fluid dynamics simulations, up to the characterization of their density profiles using Mach-Zehnder interferometry. Other optical methods such as strioscopy have been implemented to control the dynamics of the gas jet and thus define the optimal instant to perform the laser shot. The spectra obtained in different interaction conditions are presented, showing maximum energies of up to 6 MeV for protons and 16 MeV for Helium ions in the laser direction. Numerical simulations carried out with the PIC code PICLS are presented and used to discuss the different structures seen in the spectra and the underlying acceleration mechanisms.The second part presents an experiment using laser based sources generated by the ALLS laser to perform a material analysis by the Particle-induced X-ray emission (PIXE) and X-ray fluorescence (XRF) techniques. Proton and X-ray beams produced by the interaction of the laser with Aluminum, Copper and Gold targets were used to make these analyzes. The relative importance of XRF or PIXE is studied depending on the nature of the particle production target. Several spectra obtained for different materials are presented and discussed. The dual contribution of both processes is analyzed and indicates that a combination improves the retrieval of constituents in materials and allows for volumetric analysis up to tens of microns on cm^2 large areas, up to a detection threshold of ppms.
Download or read book Acc l ration Laser de Particules Charg es Et G n ration de Forts Champs Associ s Des Courants de D charge Induite Par Laser written by Michael Ehret and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work aims at both, the experimental benchmark of laser-driven ion acceleration from targets in the near-critical density regime and the exploration of laser-driven open-geometry platforms for spatial and spectral ion beam tailoring. Theoretically described mechanisms and dynamics predicted by numerical simulations are compared to novel experimental findings that are supported by new particle in cell simulations and heuristic models. Results comprise (i) demonstration of Helium ion acceleration from ultra-relativistic laser-driven near-critical density gas jet targets employing shock nozzles, (ii) further investigation of the driving mechanisms of charged particle beam lensing platforms in the quasi-static regime driven by ns-laser and in the transient regime driven by sub-ps laser, and (iii) studies of transport and tailoring of laser accelerated particle beams by electromagnetic and magnetic fields.The Helium ion source shows cut-off energies above 55MeV and peaked particle number densities of several 1e8/MeV for 22(2)MeV projectiles, a regime suitable for isotope production in alpha-therapy. Hence, the destruction of nozzles in the violent experimental environment and the perspective to high-repetition-rate operation underlines the need of mass producible nozzles with automatized nozzle exchange and vacuum systems able to maintain good vacuum levels.Ns-laser driven magnetic lenses show comparable current amplitudes in the spontaneous magnetic fields of the plasma and the consumer loop, which favors the theoretical modeling of the platform as a plasma-diode power source. During the laser drive, space charge effects arise with the arrival of the laser-plasma in vicinity of the magnetic lens, representing a possible threat to efficient lensing of ion beams. A modified target geometry is presented that decreases space charge effects.Short laser-pulse driven solid target discharge gives rise to a surficial pulsed potential dynamics guided by the target geometry. This work shows that electromagnetic discharge pulses emanating the interaction region are followed by a pulse discharge current from the ground, both transporting kA-range currents through the target rod. The observed pulsed current dynamics on timescales of tens of ps indicates the presence of a hot surface plasma. The temperature and electron density of the surface plasma are promising control parameters of the discharge pulse dispersion. The high branch of the dispersion relation is responsible for a group velocity different from the speed of light. Solutions on the low branch of the dispersion relation agree with modulations of the target potential in their spatial dimensions and temporal growth rate.Experimental and numerical studies of short laser pulse driven platforms show their applicability to spectral shaping of ion beams, with a perspective to temporal compression of beams for cases where low energy parts of the spectrum get efficiently post-accelerated. Presented are the experimental study of a simple double-coil geometry and a numerical study of a helical coil target.This work motivates junction of presented approaches for future experiments aiming at high repetition rate laser accelerated high energy density ion beams for applications, notably medical isotope production, or fundamental research, ranging from studies on collective stopping effects, warm dense matter generation to an optimized fast ignition particle injector.
Download or read book Contribution l tude de l ionisation et du chauffage des gaz par le rayonnement d un laser d clench written by Pierre Veyrie and published by . This book was released on 1968 with total page 89 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Journal de physique written by and published by . This book was released on 2003 with total page 482 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Application of Particle and Laser Beams in Materials Technology written by P. Misaelides and published by Springer Science & Business Media. This book was released on 1995-01-31 with total page 702 pages. Available in PDF, EPUB and Kindle. Book excerpt: The development of advanced materials with preselected properties is one of the main goals of materials research. Of especial interest are electronics, high-temperature and superhard materials for various applications, as well as alloys with improved wear, corrosion and mechanical resistance properties. The technical challenge connected with the production of these materials is not only associated with the development of new specialised preparation techniques but also with quality control. The energetic charged particle, electron and photon beams offer the possibility of modifying the properties of the near-surface regions of materials without seriously affecting their bulk, and provide unique analytical tools for testing their quality. Application of Particle and Laser Beams in Materials Technology provides an overview of this rapidly expanding field. Fundamental aspects concerning the interactions and collisions on atomic, nuclear and solid state scale are presented in a didactic way, along with the application of a variety of techniques for the solution of problems ranging from the development of electronics materials to corrosion research and from archaeometry to environmental protection. The book is divided into six thematic units: Fundamentals, Surface Analysis Techniques, Laser Beams in Materials Technology, Accelerator-Based Techniques in Materials Technology, Materials Modification and Synchrotron Radiation.
Download or read book ICREEC 2019 written by Ahmed Belasri and published by Springer Nature. This book was released on 2020-06-10 with total page 659 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book highlights peer reviewed articles from the 1st International Conference on Renewable Energy and Energy Conversion, ICREEC 2019, held at Oran in Algeria. It presents recent advances, brings together researchers and professionals in the area and presents a platform to exchange ideas and establish opportunities for a sustainable future. Topics covered in this proceedings, but not limited to, are photovoltaic systems, bioenergy, laser and plasma technology, fluid and flow for energy, software for energy and impact of energy on the environment.
Download or read book Dictionary of Building and Civil Engineering written by Don Montague and published by Taylor & Francis. This book was released on 1996 with total page 472 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dual-language dictionary lists over 20,000 specialist terms in both French and English, covering architecture, building, engineering and property terms. It meets the needs of all building professionals working on projects overseas. It has been comprehensively researched and compiled to provide an invaluable reference source in an increasingly European marketplace.
Download or read book International Aerospace Abstracts written by and published by . This book was released on 1966 with total page 998 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Expos s et communications pr sent s au Colloque plasmas pour lasers written by and published by . This book was released on 1975 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Quantum Mechanics Volume 3 written by Claude Cohen-Tannoudji and published by John Wiley & Sons. This book was released on 2019-12-16 with total page 790 pages. Available in PDF, EPUB and Kindle. Book excerpt: This new, third volume of Cohen-Tannoudji's groundbreaking textbook covers advanced topics of quantum mechanics such as uncorrelated and correlated identical particles, the quantum theory of the electromagnetic field, absorption, emission and scattering of photons by atoms, and quantum entanglement. Written in a didactically unrivalled manner, the textbook explains the fundamental concepts in seven chapters which are elaborated in accompanying complements that provide more detailed discussions, examples and applications. * Completing the success story: the third and final volume of the quantum mechanics textbook written by 1997 Nobel laureate Claude Cohen-Tannoudji and his colleagues Bernard Diu and Franck Laloë * As easily comprehensible as possible: all steps of the physical background and its mathematical representation are spelled out explicitly * Comprehensive: in addition to the fundamentals themselves, the books comes with a wealth of elaborately explained examples and applications Claude Cohen-Tannoudji was a researcher at the Kastler-Brossel laboratory of the Ecole Normale Supérieure in Paris where he also studied and received his PhD in 1962. In 1973 he became Professor of atomic and molecular physics at the Collège des France. His main research interests were optical pumping, quantum optics and atom-photon interactions. In 1997, Claude Cohen-Tannoudji, together with Steven Chu and William D. Phillips, was awarded the Nobel Prize in Physics for his research on laser cooling and trapping of neutral atoms. Bernard Diu was Professor at the Denis Diderot University (Paris VII). He was engaged in research at the Laboratory of Theoretical Physics and High Energy where his focus was on strong interactions physics and statistical mechanics. Franck Laloë was a researcher at the Kastler-Brossel laboratory of the Ecole Normale Supérieure in Paris. His first assignment was with the University of Paris VI before he was appointed to the CNRS, the French National Research Center. His research was focused on optical pumping, statistical mechanics of quantum gases, musical acoustics and the foundations of quantum mechanics.
Download or read book S ances pl ni res written by Société française de physique and published by . This book was released on 1973 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Theory of Ionization of Gases by Collision written by Sir John Townsend and published by . This book was released on 1910 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Guide to Nuclear Power Cost Evaluation Equipment costs written by Kaiser Engineers and published by . This book was released on 1962 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proceedings of the First International Congress of Radiation Protection written by and published by . This book was released on 1968 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
