Dissertations / Theses on the topic 'Collision spectroscopy'
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López, José G. "Theoretical studies of the dynamics and spectroscopy of weakly bound systems." Connect to resource, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1127220592.
Full textTitle from first page of PDF file. Document formatted into pages; contains xv, 99 p.; also includes graphics (some col.). Includes bibliographical references (p. 95-99). Available online via OhioLINK's ETD Center
Lin, Yawei. "Spectroscopy of High Energy Ion-neutral Collisions." Thesis, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/19720.
Full textHu, Xiao-ming. "Angle resolved photoelectron spectroscopy study of small molecules." Thesis, University of Aberdeen, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.277242.
Full textSeamons, Scott Andrew. "The collision dynamics of OH(A)+H2." Thesis, University of Oxford, 2015. http://ora.ox.ac.uk/objects/uuid:36319557-1efa-4840-8f46-c15479945a0c.
Full textNoakes, Timothy Charles Quentin. "Coaxial impact collision ion scattering spectroscopy of semiconductor and metal surfaces." Thesis, University of Warwick, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.308005.
Full textRock, Andrew Boyd, and n/a. "Low Energy Collision Induced Vibrational Relaxation in B3II+ou Iodine." Griffith University. School of Science, 1996. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20050920.144408.
Full textRock, Andrew Boyd. "Low Energy Collision Induced Vibrational Relaxation in B3II+ou Iodine." Thesis, Griffith University, 1996. http://hdl.handle.net/10072/366393.
Full textThesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Science
Full Text
Watson, Cameron William. "A study of the spectroscopy and collision dynamics of SiX (X = F,C1) radicals." Thesis, University of Edinburgh, 1995. http://hdl.handle.net/1842/14646.
Full textVerzhbitskiy, Ivan. "Spectroscopie de Raman de haute sensibilité dans des gaz à effet de serre : bandes de transitions doubles ou harmoniques." Angers, 2011. http://www.theses.fr/2011ANGE0076.
Full textThe purpose of this thesis was the understanding, viaspontaneous Raman scattering, of two types of transitions relevant to atmospheric gases: simultaneous transitions and overtone transitions. Regarding simultaneous transitions, the effort was mainly on double incoherent Raman scattering by SF6-N2, in which the two molecules simultaneously undergo a Raman-allowed transition. A highly accurate spectrum was recorded and interpreted quantum-mechanically. Agreement both in moments and in shapes was found with predictions made on the basis of a collision-induced polarizabilily model, provid€'d all Si9Sificant lo•9-ran9e contribul‹Ol0S were incorporated. The polarization mechanisms that survive in the simple model of two point-polarizable molecules were sufficient for the description of the anisotropic component, but, for the realistic description of the isotropic remnant, use of the far more sophisticated "atom-linear molecule" model was needed. In the second part of the thesis, the first overtone of the asymmetric stretch vibration, 2v3, of CO2 was studied. Unlike the previous transitions, which are collision-induced, overtones are allowed lransilions yet in the specific case of the 2v3 overtone the band was almost entirely depolarized, in agreement with the assertion (so far stated and checked for fundamental transition only) that asymmetrical vibrations give rise to depolarized lines. A rigorous protocol was applied to the interpretation of the reCOfded spectra, involving electric, optical and mechanical anharmonic effects and intermode couplings. Complete shape analysis was carried out from first principles to simulate the band profiles and the strong line-mixing effects
Dawson, Donald Frederick. "Collision-induced emission spectroscopy of small polyatomic molecules and tandem mass spectrometry of perfluorinated organics." Thesis, University of Ottawa (Canada), 2001. http://hdl.handle.net/10393/9035.
Full textKillian, Thomas Charles 1969. "1S-2S spectroscopy of trapped hydrogen : the cold collision frequency shift and studies of BEC." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/85260.
Full textConand, Clément. "Etude tectonique, pétrographique et géochimique de la zone de transition subduction-collision à Taïwan : rôle de l'héritage et de l'obliquité de la convergence." Thesis, Toulouse 3, 2019. http://www.theses.fr/2019TOU30262.
Full textThe Taiwan collision is the unique example where to examine ongoing tectonic processes at the subduction/collision transition. The oblique convergence setting allows observations of first continental accretion offshore to the mature stage of collision onshore. I show that the southern Central Range, located at the transition, exhumed petrographic assemblages with peak metamorphism increasing northwards, in a corridor characterized by left-lateral transcurrent deformation. Extension sub-parallel to the belt is also understood as a major ingredient of rock exhumation. Near the suture zone, HP rocks (12-15 kbars and 380-420 °C) associated with isolated serpentinite bodies were emplaced in association with intense ductile strain localization in the strike-slip corridor. Petrographc and geochemical analyses of the Kenting and Lichi ophiolitic mélanges reveal that these mélanges originated from the distal rifted margin and the oceanic crust of the South China Sea. I propose a 3D geodynamic model of the evolution of the Taiwan orogen in which the rifted margin architecture is taken into account and the strike-slip kinematic component of the convergence is the main driver of mountain building
Gannouni, Mohamed Achref. "Approche théorique des collisions réactives de type ion-molécule." Thesis, Paris Est, 2014. http://www.theses.fr/2014PEST1108/document.
Full textThe collision between the hydroxyl cation (OH+) and hydrogen atoms (H) plays a major role in physical chemistry of the atmosphere and astrophysics. To study this system, we generated the global three-dimensional potential energy surface (3D-PES) of the reaction H + OH+ ---- H2O+ (X2B1) ---- O + H2+. The electronic calculations were performed at the MRCI level with aug-cc-pV5Z basis including the basis set superposition error (BSSE) correction. This PES covers the molecular region and the long ranges close to the OH+ + H, O + H2+ and the hydrogen exchange channels. The quality of the PES is checked after comparison of the spectroscopic constants of H2O+ (X2B1) and of the diatomic fragments, the rovibronic levels, the dissociation energy, and the barrier to linearity of H2O+ (X2B1) to available experimental and theoretical data. A good agreement is found. Then, we used the tools of time-independent Quantum Dynamics to calculate the elastic and inelastic cross sections for the de-excitation of OH+ in collision with the hydrogen atom over a wide range of kinetic energy. We have thus determined the rotational de-excitation rate coefficients for temperatures ranging from 10 up to 200K. The results show that the inelastic cross sections on the doublet surface are on average at least two to three times larger than their cross section obtained on the previously computed cross sections using the quartet surface. Since, the long range parts of the doublet and the quartet PESs are identical, our work invalidates hence previous cross section determination. When only long range potentials are considered. Therefore, we recommend using fully the global 3D PES for scattering and reactive collision relevant for atmospheric and astrophysical studies
Ngo, Ngoc Hoa. "Profil spectral des raies d’absorption de la vapeur d'eau pour l'étude de l'atmosphère de la terre par télédétection." Thesis, Paris Est, 2013. http://www.theses.fr/2013PEST1134.
Full textThis work is devoted to a theoretical and experimental study of the spectral shape of isolated transitions of water vapor, a key species of the Earth atmosphere. The purpose of these studies is to develop an accurate line-shape model taking into account different velocity effects affecting the spectral shape of H2O lines. In the first part of this thesis, spectroscopic line parameters of pure H2O and H2O diluted in air have been measured using an external cavity diode laser and a long-path absorption cell. Different existing line-shape models have been used to adjust the measurements. The results show that the widely-used Voigt profile leads to large differences with measured spectra and that it is necessary to take into account both the velocity changes and speed dependence effects to correctly model H2O line shapes. The second part of this work is devoted to the development of a new line-shape model, based on the results obtained from classical molecular dynamics simulations and semi-classical calculations. Both collision-induced velocity changes and speed dependence effects are taken into account by this model. Furthermore, we also show that the correlation between velocity changes and internal-state changes has to be accounted for to correctly describe H2O line shapes. Spectra of pure H2O, H2O in N2 and in air, calculated with the new model are in excellent agreement with those measured by different techniques and for large ranges of pressure and spectral domain. Its complexity and its large computational cost make the new model difficult to use for practical applications such as atmospheric radiative transfer. It is thus used, in the third part, as a “benchmark” in order to test different simplified line profiles and then to choose the proper one to fit measured spectra and to be used for atmospheric spectra prediction. The results show that the pCqSDHC (partially-Correlated quadratic-Speed-Dependent Hard-Collision) model is the most adapted to represent the line shape of H2O, but also of other molecules. This model offers a very good compromise between accuracy and computation efficiency and can be easily used in different practical applications
Graham, Lisa A. (Lisa Anne) Carleton University Dissertation Chemistry. "Studies in coincidence electron spectroscopy: finite collision volume effects and the characterization of an electron momentum spectrometer." Ottawa, 1991.
Find full textLópez, José G. "Theoretical studies of the dynamics and spectroscopy of weakly bound systems." The Ohio State University, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=osu1127220592.
Full textHajsaleh, Jamal Y. (Jamal Yousef). "An Experimental Study of Collision Broadening of some Excited Rotational States of the Bending Vibration of Methyl Cyanide." Thesis, University of North Texas, 1993. https://digital.library.unt.edu/ark:/67531/metadc278369/.
Full textHolmes, Andrew J. "Studies of the spectroscopy and collision dynamics of some ion-pair states of I₂ using laser optical-optical double resonance excitation." Thesis, University of Edinburgh, 1989. http://hdl.handle.net/1842/15039.
Full textPerkins, Thomas Edward James. "The effects of electronic quenching on the collision dynamics of OH(A) with Kr and Xe." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:5998e249-35ff-4d05-9c13-9b65d59b11d9.
Full textNaylor, J. C. "The study of sputtering by concentration modulated absorption spectroscopy and the study of internal energy effects on collision induced decomposition mass spectrometry." Thesis, Swansea University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.638299.
Full textKumar, Vishant. "Fragmentation dynamics and geometrical arrangement of diatomic molecular clusters." Thesis, Normandie, 2019. http://www.theses.fr/2019NORMC245.
Full textThe analysis of a kinematically complete ion-cluster collision experiment provides insight in the dynamics of the ionized cluster dissociation. The gas phase targets allow to study the cluster in a simple environment and to determine their intrinsic properties for further condensed states. Small van der Waals clusters of N2 and CO are produced in the supersonic expansion of a gas jet and irradiated by a low energy highly charged ion beam produced by the ARIBE/GANIL facility. Using our experimental set-up COLTRIMS (COLd Target Recoil Ion Momentum Spectroscopy) it is made possible to measure in coincidence the 3-D momentum vectors of the charged fragments resulting from the collision. We have performed experiment to investigate the fragmentation dynamics and geometry of N2 and CO dimers and trimers using a projectile beam Ar9+ with the 15 qkeV energy. Following multiple electron capture, the target undergoes two or three body dissociation. For three body channels, two distinct processes have been identified in which the van der Waals and covalent bond breaks either simultaneously or sequentially. Additionally, the Coulomb explosion imaging technique has been used to determine the three dimensional structure of the N2 and CO molecular dimers and trimers. We found that the N2 and CO molecules sit perpendicularly to the dimer axis in a planar (H) or non-planar (X) configuration and that (N2)3 and (CO)3 trimers exhibit an equilateral triangular geometry
Springfield, James L. "Spectroscopy and Structure of Intermolecular Clusters and Rotational State-To-State Differential Cross-Sections for the HCI-X Collison System." Thesis, Griffith University, 2005. http://hdl.handle.net/10072/365402.
Full textThesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Science
Full Text
Bao, Zhuo. "Synchrotron Radiation Studies of Free and Adsorbed Molecules." Doctoral thesis, Uppsala University, Surface and Interface Science Division, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-8610.
Full textThis thesis contains two parts. The first part concerns the research work on free molecules using synchrotron-radiation-related techniques. Auger electron spectra of two free open-shell molecules, O2 and NO, were studied experimentally and theoretically. Photoionization experimental technique with tunable synchrotron radiation source was used to induce core-level electron ionization and obtain the KVV normal Auger electron spectra. A quantitative assignment of O2 normal Auger spectrum was obtained by applying ab initio CI calculations and LVI Auger line shape simulations including the bond length dependence of Auger transition rates. The photon energy dependence of normal Auger electron spectra was focused on with photon energies in the vicinities of core-ionization threshold energies. Consequently, the MAPCI (Molecular Auger Post Collision Interaction) theory was developed. Taking the near-threshold O2 normal Auger spectrum as an example, the two extreme cases of MAPCI effect, “atomic-like PCI” and “molecular PCI”, were discovered and discussed. The effect of shape resonance on near-threshold molecular normal Auger spectrum was discussed taking NO near threshold normal Auger spectra as example.
The second part deals with research work on the chemisorption of small epoxy organic molecules, ethylene oxide, methyl oxirane, on Si (100) surfaces. Synchrotron radiation related techniques, UPS, XPS and NEXAFS, were applied. Based on the valence photoemission spectra, C 1s and Si 2p XPS spectra, the epoxy ring opening reactions of these molecules in chemisorption process were proved. Further tentative search for the surface-adsorbate CDAD effect was performed, and no evident circular dichroism was confirmed.
Bull, James. "Application of Quantum Mechanics to Fundamental Interactions in Chemical Physics: Studies of Atom-Molecule and Ion-Molecule Interactions Under Single-Collision Conditions: Crossed Molecular Beams; Single-Crystal Mössbauer Spectroscopy: Microscopic Tensor Properties of ⁵⁷Fe Sites in Inorganic Ferrous High-Spin Compounds." Thesis, University of Canterbury. Department of Chemistry, 2010. http://hdl.handle.net/10092/4292.
Full textRenoud, Julie. "Etude expérimentale des interactions du vent solaire avec la molécule prébiotique d'hydantoine (C3N2O2H4)." Thesis, Toulouse 3, 2020. http://www.theses.fr/2020TOU30225.
Full textThis thesis presents the study of the interaction of solar wind components with the hydantoin molecule C3N2O2H4, thought to have played a role in the appearance of life on Earth. This prebiotic molecule was detected in several meteorite samples and is thus potentially present in cometary outgasing, where it interacs with solar wind composed of electrons and energetic ions. The physico-chemistry of hydantoin in interaction with 100 eV electrons, which are one of the major components of solar wind, was studied with the new experimental apparatus SWEET (Stellar Wind and Electrons interactions on astrophysical molecules - Experiment and Theory), which was set-up during this thesis in the LCAR (Laboratoire Collisions Agrégats Réactivité), within the Ion Matter Interaction team. This is a crossed-beam apparatus which enables the investigation of unique collisions between one neutral isolated molecule and one electron or ion. The coincident use of several spectrometries techniques (spectrometry of emitted and scattered electrons and ionic spectrometry by velocity map imaging and time of flight) enables the identification of ionic produced fragments, the characterisation of the fragmentation dynamics, the measurement of the energetic threshold for dissociation pathways, and the probe of molecular excited states. The results obtained on SWEET were extended to the study of the interaction of hydantoin with multi-charged minority ions of solar wind (He2+ at 8 keV and O6+ at 30 keV), studied during a measurement campaign on the COLIMACON set-up at the GANIL (Grand Accélérateur National d'Ions Lourds, Caen, France). Experimental results were completed by a quantum chemistry approach (DFT B3LYP/6-311++G(d,p)) to calculate the energy and geometry of the molecular systems as well as the dissociation potential barriers. As important results, the interaction between hydantoin and the solar wind components shows that the molecule easily fragments when multiply charged (q>+3) and the cycle opens when doubly charged, implying a high reactivity interesting within the framework of early Earth chemistry. The energetic thresholds for the major cation and dication fragmentations were measured and a theoretical reaction scheme was proposed, in accordance with the experimental measurments. The first results of the SWEET apparatus pave the way to quantitative measurements such as the absolute cross section of the observed relaxation processes, to complete the characterisation of the specific hydantoin - solar wind interaction
Davies, Julia Ann. "Electron spectroscopy of selected atmospheric molecules and hydrocarbons." Thesis, University College London (University of London), 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.283221.
Full textWilson, Emma. "Gamma spectroscopy of 207Tl126 populated in deep-inelastic collisions." Thesis, University of Surrey, 2015. http://epubs.surrey.ac.uk/807041/.
Full textChaudhry, M. A. "Electron and X-ray spectroscopy of electron-atom collisions." Thesis, University of Stirling, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.379507.
Full textBell, Ian Mac. "Alignment production by atomic collisions in a laser field." Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240609.
Full textAstill, A. G. "Spectroscopic and collision dynamic studies of Na2̲ and I2̲." Thesis, University of Sussex, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383502.
Full textThi, Ngoc Ha Tran. "Diagnostics par spectroscopies femtosecondes des caractéristiques physiques d'un milieu en combustion." Besançon, 2004. http://www.theses.fr/2004BESA2006.
Full textBaumgartner, Sean. "COLLISIONAL DEPOLARIZATION OF THE ATOMIC SODIUM 3S2S1/2 → 3P2P3/2 → 5S2S1/2 TRANSITION WITH ARGON AND XENON BUFFER GAS BY SPECTRAL HOLE-BURNING." Miami University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=miami1311956327.
Full textHedley, John. "Collisional and radiative processes in atomic spectra." Thesis, University of Newcastle Upon Tyne, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.295500.
Full textLabiad, Hamza. "Transfert d'énergie rotationnelle lors des collisions de CO-Ar et CO-H₂ à très basses températures pour des applications astrophysiques." Thesis, Rennes 1, 2017. http://www.theses.fr/2017REN1S147/document.
Full textIn the quest to understand the universe, astrophysicists observe and make models for astrophysical objects in the sky. The interstellar medium, ISM, in particular is of central importance since it represents the matter that exists in the space between stars in a galaxy, and in which stars and planets form. Understanding it, its constituents and its evolution and characteristics requires the quantification of several chemical and physical processes, including collision processes. In this work, we used the CRESU technique to reproduce very cold environments of astrophysical media, in particular dense molecular clouds in the ISM. We studied experimentally rotational energy transfer, RET, resulting from inelastic collisions at very low temperatures using a pump-probe laser-based spectroscopic technique for the purpose of measuring constants quantifying collisions. Two types of constants were determined: the first are total removal constants of RET resulting from a specific rotational quantum state to all possible final rotational quantum states, and the second are more detailed information consisting in rate constants from a specific rotational quantum state to another specific rotational quantum state, so-called state-to-state rate constants. Two experiments have been performed involving Carbone monoxide molecule, CO, as a target molecule of collisions. The first involves argon, Ar, as a projectile atom, and the second molecular hydrogen, H2, as a projectile molecule. Both collisional systems play an important role in a wide range of areas including gas-phase phenomena and astrophysical applications. In the first experiment, we investigated collisions between CO and Ar, from 293 K down to 30 K. IR-VUV double resonance technique has been exploited to measure, directly for the first time, absolute values of total removal and state-to-state constants of collisions. The experimental results have been compared to theoretical predictions based on a diatom-atom model of collision, where very good agreement was observed. In the second experiment, we investigated collisions between CO and H2 (the most abundant molecules in the ISM) from 293 K down to 5.5 K focusing on the very low temperatures of dense molecular clouds in the ISM. For the first time, total removal and state-to-state constants have been measured and compared to theoretical predictions of a highly accurate diatom-diatom model of collisions, where excellent agreement was observed. The results obtained in this thesis served to validate theoretical models of molecular collisions, helping the continuous efforts for pushing the frontiers of theoretical models. In the astrophysical side, the obtained collisional constants will be taken into account in modeling of many astrophysical media
Ezzeddine, Rana. "Le rôle des collisions avec l'hydrogène dans la determination hors-ETL de l'abondance du fer dans les étoiles froides." Thesis, Montpellier, 2015. http://www.theses.fr/2015MONTS147/document.
Full textDetermination of high precision abundances has and will always be an important goal of all spectroscopic studies. The use of LTE assumption in spectroscopic analyses has been extensively shown in the literature to badly affect the determined abundances and stellar parameters, especially in metal-poor and giant stars which can be subject to large non-LTE effects. Non-LTE modeling of stellar spectra is therefore essential to accurately reproduce the observations and derive stellar abundances. Non-LTE calculations require the inputof a bulk of atomic data, which may be subject to uncertainties. In cool stars, hydrogen collisional rates are a major source of uncertainty, which are often approximated using a classical recipe (the Drawin approximation) for allowed bound-bound, and ionization transitions only. This approximation has been shown to overestimate the collisional rates, and does not reproduce the correct behavior with energies. We demonstrate in this dissertation the inability of the Drawin approximation to describe the hydrogen collisional rates.We introduce a new method to estimate these rates based on fitting the existing quantum rates of other elements. We show that this quantum fitting method (QFM) performs well in non-LTE calculations when detailed quantum rates are not available. We test the newly proposed method, with a complete iron model atom that we developed, on a reference set of stars from the Gaia-ESO survey. Starting from well determined non-spectroscopic atmospheric parameters, we determine 1D, non-LTE, and LTE iron abundances for this set ofstars. Our non-LTE results show excellent agreement between Fe I and Fe II abundances and small line-by-line dispersions, especially for the metal-poor stars. Our method is validated upon comparison with new preliminary Fe I+H quantum calculations, whose fits show an excellent agreement with ours
Hodgkinson, Jacqueline. "Study of slow multiply charged ion-atom collisions using translational energy spectroscopy." Thesis, Queen's University Belfast, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318774.
Full textCollins, Timothy L. D. "Inelastic rotational transfer differential cross-sections for Li2-rare gas collisions." Thesis, University of Sussex, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.282082.
Full textMosely, Jacqueline Anne. "Collisional activation and target capture with massive ions by means of magnetic-sector mass spectroscopy." Thesis, University of Warwick, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263606.
Full textHultquist, Adam. "Collisional broadening by hydrogenfor stellar spectroscopy : extension towards high-lying states." Thesis, Uppsala universitet, Teoretisk astrofysik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-389326.
Full textLu, Jessica Weidgin. "Dynamics of Atmospherically Important Triatomics in Collisions with Model Organic Surfaces." Diss., Virginia Tech, 2011. http://hdl.handle.net/10919/77045.
Full textPh. D.
Wood, Mark. "Combined radiative and collisional effects in the spectrum of ytterbium." Thesis, University of Newcastle Upon Tyne, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.295510.
Full textAsplet, William. "Etude des interactions entre les défauts lacunaires et les solutés Y,O, Ti pour mieux comprendre leur rôle dans la formation des nanoparticules d'oxydes dans les aciers ODS." Thesis, Orléans, 2018. http://www.theses.fr/2018ORLE2056/document.
Full textThis PhD thesis is dedicated to the study of interaction between vacancies and Y, Ti,O solutes for a better understanding of formation of oxide nanoparticles in ODS steel (Oxide Dispersion Strengthened). These ODS steels are considered as structural material for the next generation of fission and fusion nuclear reactors. Their good properties are induced by the fine dispersion of low size oxide nanoparticles. However, obtaining this distribution is not mastered and atomic scale clustering is not yet defined. Furthermore, it was shown by theoretical models that the presence of vacancy during mechanical alloying could affect the formation of these nanoparticles. This study follows upon on a previous study made by C.He, and bring new results, new interpretation and conclusions. Some implantations with Y, Ti, O ions with several energy have been made in order to simulate the mechanical alloying step used for ODS steel fabrication. Theses irradiations have induced defects and solutes into the iron matrix. Then we characterized samples using positron annihilation spectroscopy (PAS) and secondary ion mass spectrometry (SIMS). The nature of defects was studied according to nature of the implanted ion and the annealing temperature by PAS and correlated to depth profiles of solutes obtained by SIMS. Annihilation characteristics of some defects still unknown were able to be determined thanks to positron lifetime measurements. SIMS analysis showed that titanium doesn’t migrate for annealing experiments between 100°C and 450°C and that oxygen show a complex behavior of migration and trapping dependent on the microstructure of the material. PAS results show that ionic implantations produce vacancy clusters, dislocations and solutes-vacancies complex. Their proportion changes as a function of depth and nature of these irradiations. Vacancy clusters and dislocations are detected deeper than the implantation peak with a higher fraction for the dislocations indicating that the defects were able to migrate during implantations. The fraction of vacancy-solutes complexes is the highest in the ion stopping zone and is in a good agreement with the theoretical binding energy of vacancies-solutes complex. The nature and the distribution of the defects evolve according to the annealing temperature. Vacancy clusters disappear between RT and 300°C while the dislocations are eliminated from 400°C. Oxide phases are detected for annealing at 500 and 550°C in relation with the oxygen contamination during these annealings. Some defects which the nature is not yet identified were highlighted for annealing between 300 and 400°C for Y, O and Y+O irradiations
Yamaguchi, Atsushi. "Metastable State of Ultracold and Quantum Degenerate Ytterbium Atoms: High-Resolution Spectroscopy and Cold Collisions." 京都大学 (Kyoto University), 2008. http://hdl.handle.net/2433/124352.
Full textAlagappan, Azhagammai. "Studies of collisional energy transfer in the CN radical by frequency-modulated spectroscopy." Thesis, Heriot-Watt University, 2007. http://hdl.handle.net/10399/62.
Full textKawachi, Tetsuya. "Plasma Spectroscopy of Highly Charged Ions by the Method of Collisional-Radiative Model." Kyoto University, 1995. http://hdl.handle.net/2433/160769.
Full textKyoto University (京都大学)
0048
新制・課程博士
博士(工学)
甲第6050号
工博第1447号
新制||工||990(附属図書館)
UT51-95-D369
京都大学大学院工学研究科物理工学専攻
(主査)教授 藤本 孝, 教授 大引 得弘, 教授 牧野 俊郎
学位規則第4条第1項該当
BAZALGETTE, COURREGES LACOSTE GREGORY. "Spectroscopie de tres haute resolution de icl. Photodissociation et collision de la molecule de icl orientee." Toulouse 3, 1997. http://www.theses.fr/1997TOU30224.
Full textBoumsellek, Saïd. "Etude par spectroscopie d'électrons du processus d'ionisation dans les collisions d'atomes et d'ions négatifs avec des cibles atomiques et moléculaires." Paris 11, 1989. http://www.theses.fr/1989PA112188.
Full textResults of an electron spectroscopy study of excitation and ionisation processes in S and F collisions with He, Ne, Ar, Kr, H₂, 0₂, CO₂ are presented. Results of the corresponding negative ions (S-and F-) collisions are also presented to study the two- -electron detachment. The electron spectra indicate that singly excited autoionising states of S(²D° nl et ²p° nl) et F(¹Dnl et ¹Snl) and F(¹Dnl et ¹Snl) series are populated in these collisions and this should lead to an efficient mechanism of S+ and F+ production in the range of low energies. This is a general feature conceming elements with open "p" shell. Discussion of the mechanims leading to detachment, excitation and ionisation is presented in the frame work of the Fano-Lichten promotion model using a quasi-molecular description of the collision. This indicates that quasi-molecular Auger ionisation must be the other mechanism of positive ion production. Conceming the spectroscopie character previously unknown autoionising states of (core)np series are identified. These series are forbidden in photoabsorption measurements because of the dipole selection rules. In the case of molecular targets, charge exchange to shape resonances is observed with negative ions as projectiles. Both with neutra! species and negative ions dissociative ionisation is observed
Kolbe, G. "Three level spectroscopic technique applied to collision rate and line shape determination in a plasma." Thesis, Imperial College London, 1985. http://hdl.handle.net/10044/1/37746.
Full textSekhavat, Sépanta. "Planification de mouvements sans collisions pour systèmes non holonomes." Toulouse, INPT, 1996. http://www.theses.fr/1996INPT106H.
Full textFerraton, Mathieu. "Collisions profondément inélastiques entre ions lourds auprès du Tandem d’Orsay & Spectroscopie gamma des noyaux exotiques riches en neutrons de la couche fp avec le multi-détecteur germanium ORGAM." Thesis, Paris 11, 2011. http://www.theses.fr/2011PA112119/document.
Full textThis PhD thesis was prepared within the nuclear structure group of IPN Orsay. The work presented aimed to produce neutron rich fp shell nuclei through heavy ion collisions at the tandem accelerator of IPN, and to study them using gamma spectroscopy. For this purpose, a germanium gamma array called ORGAM, and dedicated to high resolution gamma spectroscopy, was set up at the tandem accelerator. During the year 2008/2009, the individual germanium detectors were tested and repaired, as well as their ancillary anti-Compton shielding. At the same time, the liquid nitrogen auto-fill system was improved for better reliability. The array was finally set up on a beam line of the accelerator.The first experiment using the ORGAM array was performed in July 2009. This experiment aimed to study fully damped deep-inelastic collisions between a 36S beam accelerated to 154 MeV, and a 70Zn target. An additional charged particle detection system was used to detect interesting fragments emitted at backward angles. It was not possible to separate these fragments from the background induced by backscattered ions from the beam. Nevertheless, the study of gamma-gamma coincidences detected with the ORGAM array allowed to identify gamma cascades de-exciting nuclei potentially produced through the mechanism of interest. Data accumulated during another experiment performed at the tandem accelerator in 2005 were analyzed. Fusion-evaporation reaction between a 25 MeV, 14C beam focused on a 48Ca target produced the 57Cr and 59Mn nuclei, whose energy spectra were established up to 3 MeV.We attempted to study theoretically odd Chromium isotopes with a simple model based on the intermediate coupling scheme. This model, which doesn’t take into account correlation between valence nucleons, described in satisfactory way the semi-magic + 1 neutron, 53Cr, but failed to do so for mid-shell nuclei 55Cr and 57Cr