PRODUCTION ET TRANSPORT DES ETATS EXCITES DU PROJECTILE EN INTERACTION ION-SOLIDE PDF Download

Author: EMILY.. LAMOUR
Publisher:
ISBN:
Category :
Languages : fr
Pages : 0

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DANS LES COLLISIONS ION-SOLIDE, LES ETATS DE L'ION PROJECTILE DE GRAND MOMENT ANGULAIRE SCRIPT SMALL 1 SONT EN MOYENNE BEAUCOUP PLUS PEUPLES QUE LORS DES COLLISIONS ION-ATOME. L'UTILISATION D'IONS PROJECTILES AR#1#8#+ D'ENERGIE 13,6 MEV/U ET DE CIBLES SOLIDES DE CARBONE NOUS A PERMIS D'ETUDIER LES ETATS EXCITES DE L'ION AR#1#7#+ PEUPLES PAR CAPTURE. LA GAMME D'EPAISSEUR DE CIBLES CHOISIE A PERMIS D'EFFECTUER CETTE ETUDE DE LA CONDITION DE COLLISION UNIQUE (3,5 G/CM#2) JUSQU'A L'EQUILIBRE DES POPULATIONS (200 G/CM#2). NOUS AVONS OBSERVE L'EVOLUTION DES INTENSITES DES TRANSITIONS LYMAN EN FONCTION DU TEMPS DE TRANSIT DE L'ION DANS LA CIBLE (EVOLUTION SENSIBLE A LA POPULATION DES ETATS DE COEUR) AINSI QU'EN FONCTION DU TEMPS DE VOL DE L'ION DERRIERE LA CIBLE (EVOLUTION SENSIBLE A LA POPULATION DES ETATS DE RYDBERG). POUR EXPLIQUER LES RESULTATS EXPERIMENTAUX, UNE ANALYSE COMPLETE DU TRANSPORT DES ETATS EXCITES DANS LA CIBLE A ETE REALISEE. NOUS AVONS UTILISE DEUX MODELES DE TYPE COLLISIONNEL. LE PREMIER EST UN MODELE D'EQUATIONS D'EVOLUTION BASE SUR UNE DESCRIPTION STATISTIQUE DES COLLISIONS BINAIRES DU PROJECTILE AVEC LES ATOMES CIBLES. LE SECOND EST UN MODELE DE TRANSPORT CLASSIQUE BASE SUR L'EQUATION DECRIVANT LE MOUVEMENT DE L'ELECTRON PROJECTILE SUR UNE ORBITE CLASSIQUE PERTURBE PAR UNE FORCE STOCHASTIQUE. UNE COMPARAISON AVEC L'EXPERIENCE MONTRE QUE CES APPROCHES COLLISIONNELLES PERMETTENT DE REFLETER ASSEZ BIEN LA POPULATION EN MOMENT ANGULAIRE DES ETATS TRES EXCITES MAIS NETTEMENT MOINS BIEN CELLE DES ETATS DE COEUR. LE MELANGE SCRIPT SMALL 1 OBSERVE POUR CES ETATS EST BEAUCOUP PLUS IMPORTANT QUE PREVU PAR CES MODELES. LA POLARISATION DU MILIEU INDUITE PAR L'ION PROJECTILE (NON PRISE EN COMPTE PAR LES MODELES) POURRAIT ETRE RESPONSABLE D'UN TEL MELANGE PAR L'INTERMEDIAIRE DE L'EFFET STARK.

Author: CLAUDE.. FOURMENT
Publisher:
ISBN:
Category :
Languages : fr
Pages : 304

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L'ETUDE DU TRANSPORT DES ETATS EXCITES PERMET DE TESTER L'INTERACTION ION-SOLIDE ET EN PARTICULIER DE SONDER LA REPONSE DU MILIEU. DEUX SORTES DE PROCESSUS INTERVIENNENT LORS DE COLLISION ION-SOLIDE : LA SUCCESSION DE COLLISIONS BINAIRES ENTRE LES ATOMES DU SOLIDE ET L'ION PROJECTILE, ET SON INTERACTION AVEC LE CHAMP DE POLARISATION (CHAMP DE SILLAGE) QU'IL INDUIT DANS LE GAZ D'ELECTRONS DU MILIEU. NOUS AVONS ETABLI L'EQUATION PILOTE QUI REGIT L'EVOLUTION DE LA MATRICE DENSITE DES ETATS ELECTRONIQUES INTERNES D'UN ION HYDROGENOIDE LOURD ET RAPIDE DANS UN SOLIDE EN TENANT COMPTE DE CES DEUX PROCESSUS. NOUS PRESENTONS UNE ANALYSE QUANTITATIVE DE L'INFLUENCE DES PARAMETRES INTERVENANT DANS LA DESCRIPTION DU TRANSPORT. EN PARTICULIER LE CHAMP DE SILLAGE EST RESPONSABLE D'UN MELANGE COHERENT ENTRE NIVEAUX QUASI DEGENERES DONT LES MANIFESTATIONS EXPERIMENTALES SONT RICHES D'INFORMATIONS QUANT AU PEUPLEMENT DES ETATS EXCITES ET A LA REPONSE DU MILIEU. EXPERIMENTALEMENT, DES TECHNIQUES DE SPECTROSCOPIE X A HAUTE RESOLUTION SONT UTILISEES POUR OBSERVER L'EVOLUTION DES POPULATIONS DES NIVEAUX NP (2N5) AINSI QUE DE CERTAINS NIVEAUX DE STRUCTURE FINE DU PROJECTILE EN FONCTION DE L'EPAISSEUR DE CIBLE TRAVERSEE. L'ETUDE EXPERIMENTALE COMPLETE DES SYSTEMES COLLISIONNELS KR 3 5 + C ET A1 (E=60 MEV/A) OU LES ETATS EXCITES SONT INITIALEMENT PEUPLES PAR SIMPLE EXCITATION EST PRESENTEE. LE MODELE THEORIQUE D'EQUATION PILOTE REPRODUIT TRES BIEN CES RESULTATS EXPERIMENTAUX, AINSI QUE CEUX PROVENANT D'ETUDES PRECEDENTES OU LES ETATS EXCITES ETAIENT INITIALEMENT PEUPLES PAR CAPTURE ELECTRONIQUE MECANIQUE (MEC). LA COMPARAISON EXPERIENCE-THEORIE NOUS PERMET D'AVOIR ACCES A DES PARAMETRES CLEFS DE L'EVOLUTION DES ETATS EXCITES DU PROJECTILE COMME LA VALEUR DU CHAMP DE SILLAGE INDUIT ( 10 9V.CM 1) ET SA VARIATION SPATIALE A L'ECHELLE DES ORBITES ATOMIQUES, ET D'AUTRE PART DE TESTER LES CONDITIONS INITIALES AVANT TRANSPORT EN TERMES DE SECTIONS EFFICACES ET DE COHERENCES COLLISIONNELLES.

Author: C.T. Whelan
Publisher: Springer Science & Business Media
ISBN: 9780306461811
Category : Science
Languages : en
Pages : 392

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Book Description
The last few years have seen some remarkable advances in the understanding of atomic phenomena. It is now possible to isolate atomic systems in traps, measure in coincidence the fragments of collision processes, routinely produce, and study multicharged ions. One can look at bulk matter in such a way that the fundamental atomic character is clearly evident and work has begun to tease out the properties of anti matter. The papers in this book reflect many aspects of modem Atomic Physics. They correspond to the invited talks at a conference dedicated to the study of "New Directions in Atomic Physics," which took place in Magdalene College, Cambridge in July of 1998. The meeting was designed as a way of taking stock of what has been achieved and, it was hoped, as a means of stimulating new research in new areas, along new lines. Consequently, an effort was made to touch on as many directions as we could in the four days of the meeting. We included some talks which overviewed whole subfields, as well as quite a large number of research contributions. There is a unity to Physics and we tried to avoid any artificial division between theory and experiment. We had roughly the same number of talks from those who are primarily concerned with making measurements, and from those who spend their lives trying to develop the theory to describe the experiments.

Author: GARY S. WAS
Publisher: Springer
ISBN: 1493934384
Category : Technology & Engineering
Languages : en
Pages : 1014

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The revised second edition of this established text offers readers a significantly expanded introduction to the effects of radiation on metals and alloys. It describes the various processes that occur when energetic particles strike a solid, inducing changes to the physical and mechanical properties of the material. Specifically it covers particle interaction with the metals and alloys used in nuclear reactor cores and hence subject to intense radiation fields. It describes the basics of particle-atom interaction for a range of particle types, the amount and spatial extent of the resulting radiation damage, the physical effects of irradiation and the changes in mechanical behavior of irradiated metals and alloys. Updated throughout, some major enhancements for the new edition include improved treatment of low- and intermediate-energy elastic collisions and stopping power, expanded sections on molecular dynamics and kinetic Monte Carlo methodologies describing collision cascade evolution, new treatment of the multi-frequency model of diffusion, numerous examples of RIS in austenitic and ferritic-martensitic alloys, expanded treatment of in-cascade defect clustering, cluster evolution, and cluster mobility, new discussion of void behavior near grain boundaries, a new section on ion beam assisted deposition, and reorganization of hardening, creep and fracture of irradiated materials (Chaps 12-14) to provide a smoother and more integrated transition between the topics. The book also contains two new chapters. Chapter 15 focuses on the fundamentals of corrosion and stress corrosion cracking, covering forms of corrosion, corrosion thermodynamics, corrosion kinetics, polarization theory, passivity, crevice corrosion, and stress corrosion cracking. Chapter 16 extends this treatment and considers the effects of irradiation on corrosion and environmentally assisted corrosion, including the effects of irradiation on water chemistry and the mechanisms of irradiation-induced stress corrosion cracking. The book maintains the previous style, concepts are developed systematically and quantitatively, supported by worked examples, references for further reading and end-of-chapter problem sets. Aimed primarily at students of materials sciences and nuclear engineering, the book will also provide a valuable resource for academic and industrial research professionals. Reviews of the first edition: "...nomenclature, problems and separate bibliography at the end of each chapter allow to the reader to reach a straightforward understanding of the subject, part by part. ... this book is very pleasant to read, well documented and can be seen as a very good introduction to the effects of irradiation on matter, or as a good references compilation for experimented readers." - Pauly Nicolas, Physicalia Magazine, Vol. 30 (1), 2008 “The text provides enough fundamental material to explain the science and theory behind radiation effects in solids, but is also written at a high enough level to be useful for professional scientists. Its organization suits a graduate level materials or nuclear science course... the text was written by a noted expert and active researcher in the field of radiation effects in metals, the selection and organization of the material is excellent... may well become a necessary reference for graduate students and researchers in radiation materials science.” - L.M. Dougherty, 07/11/2008, JOM, the Member Journal of The Minerals, Metals and Materials Society.

Author: Andrew Zangwill
Publisher: Cambridge University Press
ISBN: 1316583260
Category : Science
Languages : en
Pages : 470

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Physics at Surfaces is a unique graduate-level introduction to the physics and chemical physics of solid surfaces, and atoms and molecules that interact with solid surfaces. A subject of keen scientific inquiry since the last century, surface physics emerged as an independent discipline only in the late 1960s as a result of the development of ultra-high vacuum technology and high speed digital computers. With these tools, reliable experimental measurements and theoretical calculations could at last be compared. Progress in the last decade has been truly striking. This volume provides a synthesis of the entire field of surface physics from the perspective of a modern condensed matter physicist with a healthy interest in chemical physics. The exposition intertwines experiment and theory whenever possible, although there is little detailed discussion of technique. This much-needed text will be invaluable to graduate students and researchers in condensed matter physics, physical chemistry and materials science working in, or taking graduate courses in, surface science.

Author: Ervin B. Podgorsak
Publisher: Springer Science & Business Media
ISBN: 3642008755
Category : Science
Languages : en
Pages : 774

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This book summarizes basic knowledge of atomic, nuclear, and radiation physics that professionals need for efficient and safe use of ionizing radiation. Concentrating on the underlying principles of radiation physics, it covers prerequisite knowledge for medical physics courses on the graduate and post-graduate levels, providing the link between elementary physics on the one hand and the intricacies of the medical physics specialties on the other.

Author: P. Misaelides
Publisher: Springer Science & Business Media
ISBN: 9780792333241
Category : Science
Languages : en
Pages : 702

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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.

Author: Jostein Gaarder
Publisher: Farrar, Straus and Giroux
ISBN: 1466804270
Category : Fiction
Languages : en
Pages : 735

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A page-turning novel that is also an exploration of the great philosophical concepts of Western thought, Jostein Gaarder's Sophie's World has fired the imagination of readers all over the world, with more than twenty million copies in print. One day fourteen-year-old Sophie Amundsen comes home from school to find in her mailbox two notes, with one question on each: "Who are you?" and "Where does the world come from?" From that irresistible beginning, Sophie becomes obsessed with questions that take her far beyond what she knows of her Norwegian village. Through those letters, she enrolls in a kind of correspondence course, covering Socrates to Sartre, with a mysterious philosopher, while receiving letters addressed to another girl. Who is Hilde? And why does her mail keep turning up? To unravel this riddle, Sophie must use the philosophy she is learning—but the truth turns out to be far more complicated than she could have imagined.

Author: Debbie Stokes
Publisher: John Wiley & Sons
ISBN: 0470065400
Category : Science
Languages : en
Pages : 247

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Offers a simple starting point to VPSEM, especially for new users, technicians and students containing clear, concise explanations Crucially, the principles and applications outlined in this book are completely generic: i.e. applicable to all types of VPSEM, irrespective of manufacturer. Information presented will enable reader to turn principles into practice Published in association with the Royal Microscopical Society (RMS) -www.rms.org.uk

Author:
Publisher:
ISBN:
Category : Nuclear energy
Languages : en
Pages : 1858

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