Log in

Relevant bibliographies by topics / Electron scattering / Dissertations / Theses

Dissertations / Theses on the topic 'Electron scattering'

To see the other types of publications on this topic, follow the link: Electron scattering.

Author: Grafiati

Published: 4 June 2021

Last updated: 20 February 2023

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 50 dissertations / theses for your research on the topic 'Electron scattering.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.

1

Slaughter, Daniel Stephen, and d. slaughter@aip org au. "Superelastic Electron Scattering from Caesium." Flinders University. Chemistry Physics and Earth Sciences, 2007. http://catalogue.flinders.edu.au./local/adt/public/adt-SFU20071009.100421.

Full text

Abstract:

This thesis describes an experimental study of superelastic electron scattering from the 6^2P_3/2 state of caesium. The present status of electron-atom collision studies is initially reviewed and the motivation behind the current work is then presented. A description of the theoretical framework is subsequently provided in the context of the present experimental study, followed by an overview of the several theoretical approaches for describing electron-atom interactions which are currently available. The apparatus and experimental setup used throughout the project are also described in detail. Technical specifications and data are provided, including diagrams (where appropriate) for a laser frequency locking system, electron gun and spectrometer, atomic beam source and data acquisition system. The experimental procedures are explained and discussed, including a detailed analysis of the optical pumping process required to excite the atomic target. A substantial component of this project was to address several potential sources of systematic error and to reduce these wherever possible. All of the errors and uncertainties relevant to the experiment are discussed in chapter 5. In chapter 6 the results of the present superelastic electron scattering experiments are reported for incident electron energies of 5.5eV, 8.5eV and 13.5eV, corresponding to superelastic electron energies of 7eV, 10eV and 15eV. These results are presented as three reduced Stokes parameters, P1, P2, P3 and a coherence parameter, P+ . For comparison, predictions from a number of currently available theories are presented alongside the experimental results. Finally, conclusions are drawn on this work in the context of the current status of electron-atom scattering from alkali-metals.

APA, Harvard, Vancouver, ISO, and other styles

2

Scholz, Timothy Theodore. "Electron scattering by atomic hydrogen." Thesis, Queen's University Belfast, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335441.

Full text

APA, Harvard, Vancouver, ISO, and other styles

3

Duddy, Pamela E. "Electron scattering by molecular oxygen." Thesis, Queen's University Belfast, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.287611.

Full text

APA, Harvard, Vancouver, ISO, and other styles

4

Thomas, Malcolm. "Electron scattering by atomic oxygen." Thesis, Queen's University Belfast, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337031.

Full text

APA, Harvard, Vancouver, ISO, and other styles

5

Little, D. A. "Electron-N₂⁺ scattering and dynamics." Thesis, University College London (University of London), 2015. http://discovery.ucl.ac.uk/1464074/.

Full text

Abstract:

Molecular nitrogen, N₂, is the most abundant molecule in the terrestrial atmosphere. Its cation N₂⁺ is therefore prevalent in the earth's ionosphere as well as in nitrogen plasmas produced for reasons varying from lightning strikes to combustion. Any model which seeks to describe plasmas in air must contain a description of nitrogen ion chemistry. Despite this, there is a distinct paucity of data describing electron-N₂⁺ interactions and the resultant bound and quasi-bound electronic structure of N₂. The characterisation of these states is essential for describing dissociative recombination which is the main destroyer of molecular ions in a plasma. This thesis aims to alleviate this problem by performing extensive ab initio R-matrix calculations to create a comprehensive map of the highly-excited electronic structure of N₂ which can the be used to perform a dissociative recombination cross-section calculation. Potential energy curves were found by performing resonant and bound state calculations for all singlet and triplet molecular symmetries of N₂ up to l ≤ 4. The use of a dense grid meant that highly-excited electronic states could be found with an unprecedented level of detail. Many of the states were previously unknown. A new fitting method was developed for the characterisation of resonant states using the time-delay method. It was shown that whilst the R-matrix method is not competitive with conventional quantum chemistry techniques for low lying valence states, it is particularly appropriate for highly-excited states, such as Rydberg states. The data gained from these calculations was then used as an input for a multichannel quantum defect theory calculation of a dissociative recombination cross-section. A description is given of how to prepare the data from the R-matrix calculation for input into a multichannel quantum defect theory dissociative recombination cross-section calculation. Cross-sections were found for v=0-3 including three ionic cores. Whilst previous studies of dissociative recombination using R-matrix data required some empirical intervention, the cross-section found in this thesis is completely ab initio and is in good agreement with experiment.

APA, Harvard, Vancouver, ISO, and other styles

6

Hoffmeyer, Ruth Ellen. "High-energy electron scattering from molecules." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ35471.pdf.

Full text

APA, Harvard, Vancouver, ISO, and other styles

7

Hopkins, P. J. B. "Nuclear cluster structure and electron scattering." Thesis, University of Oxford, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376916.

Full text

APA, Harvard, Vancouver, ISO, and other styles

8

Palmer, R. E. "Inelastic electron scattering by physisorbed molecules." Thesis, University of Cambridge, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383837.

Full text

APA, Harvard, Vancouver, ISO, and other styles

9

Osborn, Matthew C. 1970. "Kinematic scaling in quasielastic electron scattering." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/35043.

Full text

APA, Harvard, Vancouver, ISO, and other styles

10

Guinea, William Edward. "Polarisation and Alignment Studies in Electron Scattering From Rubidium." Thesis, Griffith University, 2009. http://hdl.handle.net/10072/367197.

Full text

Abstract:

Measurements have been made of the A2 spin asymmetry in the scattering of polarised electrons from rubidium atoms. Results have been taken at an incident energy of 15, 20, 30, 50 and 80eV for elastic scattering, and at 15, 20, 30 and 50eV for 5S to 5P excitation where the fine structure has not been resolved. The measurements covered the angular range 30° to 110°. Results were taken using a crossed beam type experiment, with a hemispherical electrostatic detector. Polarised electrons were provided by a conventional gallium arsenide spin-polarised electron source. The Rmatrix and relativistic distorted wave calculations available demonstrate good agreement with the experimental results, though there are some clear discrepancies between the magnitudes and positions of the extrema as predicted by theory. These A2 results follow on from those taken by Went (2003). A study of the autoionisation resonances of rubidium has also been undertaken. This consisted of first measuring the angular variation of the autoionisation resonances in the angular range 30° to 130°, at an incident energy of 1keV. A crossed beam method was also used for these results, though electrons were provided by a conventional electron gun. Significant relative angular variation between sets of autoionisation resonances was observed. The results taken represent the first experimentally determined values of the alignment parameter, A20 and R0, the isotropic distribution ratio for the leading autoionisation doublet of rubidium. The experimentally determined values of A20 and R0 were not inconsistent with the theoretical values available for comparison. Finally an attempt was made to measure a circular dichroism in the angular distribution of autoionised electrons due to stepwise laser/electron impact excitation (CPDAD). The experimental detection of such a circular dichroism would be the very first of its kind. Such a measurement would also help validate the theoretical approach that predicted its existence. Preliminary investigation requires identification of an autoionisation resonance that is enhanced with the stepwise excitation procedure. A crossed beam experiment identical to the procedure immediately above was undertaken using a conventional electron gun. Laser light resonant with the D2 line of rubidium was provided by a titanium-sapphire laser, while a diode laser was used to repump the dark state. Measurements were taken at incident energies of 250, 450, 700 and 1000eV at ejected electron angles of 75°, 75°, 90° and 90° respectively. No enhancement was visible with the stepwise process for any of the observed autoionisation resonances, so it was not possible to study CPDAD.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Biomolecular and Physical sciences
Science, Environment, Engineering and Technology
Full Text

APA, Harvard, Vancouver, ISO, and other styles

11

Jansen, Richard-Jan Engel. "Electron transport and scattering in the 2DEG base hot-electron transistor." Thesis, University of Cambridge, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389876.

Full text

APA, Harvard, Vancouver, ISO, and other styles

12

Hyldgaard, Per. "Noneqilibrium Electron-Electron Scattering in Possible Far-Infrared Quantum Cascade Laser." The Ohio State University, 1995. http://rave.ohiolink.edu/etdc/view?acc_num=osu1392908012.

Full text

APA, Harvard, Vancouver, ISO, and other styles

13

Hyldgaard, Per. "Nonequilibrium electron-electron scattering in possible far-infrared quantum cascade laser /." The Ohio State University, 1995. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487929745336983.

Full text

APA, Harvard, Vancouver, ISO, and other styles

14

au, kaurgurd@willettonshs wa edu, and Gurdeep Kaur. "Electron-helium scattering using analytical and numerical wave functions." Murdoch University, 2002. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20080123.100101.

Full text

Abstract:

Theoretical investigations of electron-inert gas scattering are challenging because of the complex target structure. The electron-Helium system has been the most studied both at low and intermediate energies by sophisticated R-matrix and coupled channels methods. For the other inert gases, few calculations have been attempted at the same level sophistication. One problem is that general target-structure codes provide different forms of wave functions that must be interfaced with the scattering equations. The theoretical work presented in this thesis is based on the momentum-space coupled channels equations. For this formalism only one and two-electron atoms have been studied and purpose-built routines, specific to these atoms, have been developed. For the inert gases however such a task is much more formidable and a more practical approach is to use existing structure codes that have taken several man-years to develop. The framework of this thesis comprises of two parts. In the first part we discuss the need for, and the way to, modify the existing close-coupling code developed by Berge & Stelbovics in order to interface with other atomic structure packages in the literature. Two mainstream packages, an atomic structure package of Charlotte Froese Fischer and an atomic structure of Alan Hibbert are discussed. Methods to extract the wave functions for Helium and Neon targets using Hibbert's package are given. In the second part, various options and strategies for the calculation of the target structure, including frozen-core and configuration-interaction wave functions, using analytic Slater, Laguerre or numerical orbitals are considered for the Helium target. Hibbert's structure code wave functions are shown to be correctly interfaced into our momentum-space coupled channels code. The pros and cons of the various target structure descriptions are given and applied for lowenergy elastic and inelastic scattering of electron from Helium.

APA, Harvard, Vancouver, ISO, and other styles

15

Helme, Lucy. "Neutron Scattering Studies of Correlated Electron Systems." Thesis, University of Oxford, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.491531.

Full text

Abstract:

This thesis presents neutron scattering studies of three correlated electron systems, each of which exhibit different competing interactions. These include charge order, magnetic order and lattice degrees of freedom. The main focus is on magnetic excitations within the systems. In all cases the experimental data have been analysed through comparison with theoretical models. Chapter 3 presents an investigation into the Jahn-Teller effect in the rare earth oxide Pr02, through inelastic neutron scattering studies of the crystal field transitions above and below a static structural distortion temperature. The data are compared with a point-charge model of the crystal field levels. \Ve conclude that the observed temperature evolution of the crystal field levels originates from the structural distortion due to the Jahn-Teller effect. Chapter 4 describes studies of magnetic excitations in the layered charge-ordered transition-metal oxide La1.5Sro.5Co04 through inelastic neutron scattering studies, and subsequent comparison with spin-wave dispersion models. It was found that the spin-wave excitations were decoupled from the charge order. Inclusion of the strong crystal anisotropy was necessary in order to successfully describe the data. Chapters 5 and 6 present studies of the magnetically ordered phase of Nax Co02 with x rv 0.75, a metallic layered transition-metal oxide. Chapter 5 describes investigations into the magnetic excitations in the compound, which were successfully modelled by linear spin-wave theory, including terms for the anisotropy. The excitations were found to be highly three dimensional despite the layered nature of the crystal structure. Chapter 6 presents a diffraction study of a spin-flop transition in an applied magnetic field, which confirmed the magnetic order. The transition field was found to be in excellent agreement with the exchange and anisotropy parameters extracted in chapter 5.

APA, Harvard, Vancouver, ISO, and other styles

16

Plamann, Tobias. "Dynamical scattering in super-resolution electron microscopy." Thesis, University of Cambridge, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.396094.

Full text

APA, Harvard, Vancouver, ISO, and other styles

17

Hatton, D. C. "Spin polarized electron scattering at ferromagnetic interfaces." Thesis, University of Cambridge, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.603854.

Full text

APA, Harvard, Vancouver, ISO, and other styles

18

Dwyer, C. "Scattering theory for advanced transmission electron microscopy." Thesis, University of Cambridge, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.598710.

Full text

Abstract:

Aspects of a theoretical and computational basis for the simulation of fast electron scattering in a solid due to elastic, electron-phonon and atomic ionisation events are developed. The primary motivation for this work arises from the need for detailed simulations of fast electron scattering to assist in the quantitative interpretation of experimental data acquired using high-spatial-resolution analytical techniques in the scanning transmission electron microscope. The scattering behaviour of Å-scale electron probes in simple atomic structures is examined with specific reference to the origin of core energy-loss signals and the spatial resolution of annular dark-field images generated by such probes. A multiscale theory of the dynamical elastic and inelastic scattering of fast electrons is then developed. This theory is applicable to many forms of inelastic scattering, and is developed in the form of a multi-dimensional extension of the well-known multislice theory of dynamical elastic scattering of fast electrons. Methods for obtaining the key quantities required for the application of this theory to the inelastic scattering of fast electrons due to atomic ionisation are presented. One of these methods is extended to enable the inclusion of relativistic effects in the ionisation process. A preliminary test of the multislice theory is made by comparing calculated and experimental characteristic-loss electron diffraction patterns acquired from silicon. The treatment of incoherent electron waves using Monte Carlo integration, which in certain circumstances can reduce computation time dramatically, is also demonstrated. Finally, the predictions of the theory are compared with those of approximate methods for calculating the origin of the core energy-loss signal in the scanning transmission electron microscope.

APA, Harvard, Vancouver, ISO, and other styles

19

Lee, Shun-Chen. "Electron scattering processes in semiconductor quantum wells." Thesis, Heriot-Watt University, 1997. http://hdl.handle.net/10399/661.

Full text

APA, Harvard, Vancouver, ISO, and other styles

20

Smith, Ian M. "Electron scattering by chiral and oriented molecules." Thesis, Queen's University Belfast, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263513.

Full text

APA, Harvard, Vancouver, ISO, and other styles

21

Mohanmurthy, Prajwal. "Topics on electron,neutrino and axion scattering." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/103161.

Full text

Abstract:

Thesis: S.M., Massachusetts Institute of Technology, Department of Physics, 2015.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 61-64).
Under the broad topic of scattering, in this thesis we particularly investigate Lorentz invariance using Compton Scattering at the Compton Polarimeter located in Hall-C at Thomas Jefferson National Accelerator Facility. The Mississippi State Axion Search, an axion search experiment which uses light shining through a wall technique is described in detail, including its instrumentation, initial tests and future impact. Furthermore, a novel method of detection of solar anti-neutrinos based on coherent neutrino scattering is described. Additionally, on the instrumentation side, development of a multi-purpose beam instrument based on synchrotron light to measure the electron beam polarization, beam profile and intensity at the future Electron Ion Collider is presented.
by Prajwal Mohanmurthy.
S.M.

APA, Harvard, Vancouver, ISO, and other styles

22

Zammit, Mark Christian. "Electron and positron scattering from diatomic molecules." Thesis, Curtin University, 2015. http://hdl.handle.net/20.500.11937/1935.

Full text

Abstract:

This thesis describes the development of the adiabatic-nuclei convergent close-coupling method and its application to positron scattering from vibrationally excited molecular hydrogen H2 and electron scattering from the vibrationally excited molecular hydrogen ion H2+ and its isotopologues (D2+, T2+, HD+, HT+ and TD+). For the first time, convergence is achieved in both the fixed-nuclei close-coupling (target state) and projectile partial-wave expansions. Results are also in excellent agreement with experiment.

APA, Harvard, Vancouver, ISO, and other styles

23

Napier, Stuart A. "Electron correlation and spin-dependent effects in the electron impact excitation of zinc atoms." University of Western Australia. School of Physics, 2009. http://theses.library.uwa.edu.au/adt-WU2009.0098.

Full text

Abstract:

[Truncated abstract] This work investigated electron correlation and spin-dependent effects in electron scattering from zinc for incident electron energies from the lowest excitation threshold at 4.003 eV to 50 eV. Experiments were performed using a crossed-beams electron impact spectrometer, which included an unpolarised electron gun, and also a spin-polarised electron gun. The apparatus was tested, and shown to be operating well, by repeating past studies of electron scattering from helium and argon. Emission cross sections for the 4s4p 3P1, 4s4p 1P1, 4s5s 3S1, 4s4d; 5d; 6d 3D1;2;3 and 4s4d; 5d 1D2 states were measured from the respective thresholds to 50 eV. These were compared with Convergent Close-Coupling (CCC) and B-spline R-matrix (BSRM) calculations of the 4s4p 3P1, 4s4p 1P1, 4s5s 3S1, 4s4d 1D2 and 4s4d 3D1;2;3 emission cross sections. There are serious discrepancies between the theories, and between the theories and experiment, which indicates strong continuum coupling and innershell excitation effects in the electron excitation of zinc. The differential elastic scattering signal at scattering angles of 30 , 54 , 90 and 110 was measured for incident electron energies from just below the lowest excitation threshold at 4.003 eV, to the ionisation threshold at 9.394 eV. Some assignments given by Sullivan et al [1] and Zatsarinny and Bartschat [2] were confirmed by the present experiment. An area of disagreement in the literature concerning the nature of a feature observed at the 4s4p 1P1 threshold at 5.796 eV was resolved in favour of Zatsarinny and Bartschat, who assign the feature as a cusp. ... Below the ionisation threshold, the 4s4p 3P1 photon excitation function supports the assignment of the near-4s4p 1P1 threshold feature as a cusp. Some of the overlapping negative-ion resonances which were observed near 7.5 eV in the 4s4p 3P1, 4s4p 1P1 and 4s5s 3S1 photon excitation functions were assigned with the assistance of the BSRM calculations of Zatsarinny and Bartschat. However, continuum coupling effects above 8 eV seem to cause the theoretical negative-ion resonance predictions to break down. Above the ionisation threshold, the near-11 eV negative-ion resonance effects depend on the configuration n, L and S of the neutral state excitation observed. This may be due to the properties of the mixed negative ion component states. Postcollision interaction (PCI) effects the 4s5s 3S1, 4s4d; 5d; 6d 3D1;2;3 and 4s4d; 5d 1D2 photon excitation functions. The PCI mechanism can populate the 4s4d; 5d; 6d 3D1;2;3 and 4s4d; 5d 1D2 states because the scattered and ejected electrons have a similar energy, and can thus exchange a large amount of orbital angular momentum. The present work demonstrates that electron correlation effects, especially those associated with innershell excitation, are very significant in electron scattering from zinc. Existing theoretical models of electron scattering from zinc inadequately treat electron correlations, and as a result of this are inaccurate, as shown here. The studies presented here should guide the development of models that accurately describe the innershell excitation effects, which are important for zinc and a great many other atoms.

APA, Harvard, Vancouver, ISO, and other styles

24

Shackleton, Anthony Edward. "Investigations of the Temkin-Poet model for electron-hydrogen iso-electronic series scattering." Thesis, Shackleton, Anthony Edward (2004) Investigations of the Temkin-Poet model for electron-hydrogen iso-electronic series scattering. PhD thesis, Murdoch University, 2004. https://researchrepository.murdoch.edu.au/id/eprint/303/.

Full text

Abstract:

An important model in the study of electron-atom collisions was development by Temkin and Poet. Although the model has been used to test many theories and approximation methods, the novel method of solution used by Poet has not been developed further to any great extent. The Temkin-Poet model of electron scattering simplifies the three-body scattering problem by suppressing all angular dependence of the wavefunction. In this thesis we return to Poet's method and apply it to a range of calculations for the hydrogen-isoelectronic series. Firstly it is demonstrated that the method provides high-precision solutions for elastic and inelastic scattering. these solutions will then be used to investigate various aspects of electron scattering including the ionisation of hydrogen in the near-threshold region, resonant states in helium, and the scaling of elastic cross sections for a number of hydrogen-like ions.

APA, Harvard, Vancouver, ISO, and other styles

25

Shackleton, Anthony Edward. "Investigations of the Temkin-Poet model for electron-hydrogen iso-electronic series scattering." Shackleton, Anthony Edward (2004) Investigations of the Temkin-Poet model for electron-hydrogen iso-electronic series scattering. PhD thesis, Murdoch University, 2004. http://researchrepository.murdoch.edu.au/303/.

Full text

Abstract:

An important model in the study of electron-atom collisions was development by Temkin and Poet. Although the model has been used to test many theories and approximation methods, the novel method of solution used by Poet has not been developed further to any great extent. The Temkin-Poet model of electron scattering simplifies the three-body scattering problem by suppressing all angular dependence of the wavefunction. In this thesis we return to Poet's method and apply it to a range of calculations for the hydrogen-isoelectronic series. Firstly it is demonstrated that the method provides high-precision solutions for elastic and inelastic scattering. these solutions will then be used to investigate various aspects of electron scattering including the ionisation of hydrogen in the near-threshold region, resonant states in helium, and the scaling of elastic cross sections for a number of hydrogen-like ions.

APA, Harvard, Vancouver, ISO, and other styles

26

Eggeling, Joachim. "Inelastic electron scattering from adsorbate covered semiconductor surfaces." Thesis, Imperial College London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.313773.

Full text

APA, Harvard, Vancouver, ISO, and other styles

27

Harris, Simon Michael. "Resonant electron scattering phenomena in molecule-surface systems." Thesis, University of Liverpool, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.283046.

Full text

APA, Harvard, Vancouver, ISO, and other styles

28

Baba-Kishi-Zadeh, K. "Crystallographic information from electron back-scattering diffraction patterns." Thesis, University of Bristol, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.375379.

Full text

APA, Harvard, Vancouver, ISO, and other styles

29

Hock, Kai Meng. "Low energy electron scattering from molecules on surfaces." Thesis, University of Cambridge, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240119.

Full text

APA, Harvard, Vancouver, ISO, and other styles

30

Barnard, John Cameron. "Low energy electron scattering by ordered adsorbed molecules." Thesis, University of Cambridge, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.321430.

Full text

APA, Harvard, Vancouver, ISO, and other styles

31

Diaconescu, Luca Radu McKeown R. D. "Applications of effective field theory to electron scattering /." Diss., Pasadena, Calif. : California Institute of Technology, 2005. http://resolver.caltech.edu/CaltechETD:etd-03082005-201156.

Full text

APA, Harvard, Vancouver, ISO, and other styles

32

au, optimusmaximus@westnet com, and Anthony Edward Shackleton. "Investigations of the Temkin-Poet Model for Electron-Hydrogen Iso-Electronic Series Scattering." Murdoch University, 2004. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20050310.94104.

Full text

Abstract:

An important model in the study of electron-atom collisions was development by Temkin and Poet. Although the model has been used to test many theories and approximation methods, the novel method of solution used by Poet has not been developed further to any great extent. The Temkin-Poet model of electron scattering simplifies the three-body scattering problem by suppressing all angular dependence of the wavefunction. In this thesis we return to Poet's method and apply it to a range of calculations for the hydrogen-isoelectronic series. Firstly it is demonstrated that the method provides high-precision solutions for elastic and inelastic scattering. these solutions will then be used to investigate various aspects of electron scattering including the ionisation of hydrogen in the near-threshold region, resonant states in helium, and the scaling of elastic cross sections for a number of hydrogen-like ions.

APA, Harvard, Vancouver, ISO, and other styles

33

Memarian, Fereshteh Memarian. "EFFECT OF ELECTRON-ELECTRON SCATTERING ON LINEAR CONDUCTIVITY FOR GRAPHENE-LIKE BAND STRUCTURE." University of Akron / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=akron1532977274517365.

Full text

APA, Harvard, Vancouver, ISO, and other styles

34

Gagliardi, Alessio. "Theoretical modeling and simulation of electron-phonon scattering processes in molecular electronic devices." [S.l.] : [s.n.], 2007. http://deposit.ddb.de/cgi-bin/dokserv?idn=98556282X.

Full text

APA, Harvard, Vancouver, ISO, and other styles

35

莫卓威 and Cheuk-wai Mok. "Comparing electron and positron scattering factors for applications indiffraction and holography." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1997. http://hub.hku.hk/bib/B31214459.

Full text

APA, Harvard, Vancouver, ISO, and other styles

36

Deniz, Muhammed. "Measurement Of Sm Electro-weak Parameters In Reactor Antineutrino-electron Scattering In Texono Experiment." Phd thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/12608386/index.pdf.

Full text

Abstract:

In this thesis a search for electron type neutrino-electron scattering cross-section and Weinberg Angle measurements were performed at KS Nuclear Power Station with 200 kg CsI(Tl) scintillating crystal detector located at a distance of 28 m from the 2.9 GW reactor core giving total flux of 6:52X10^12 cm^-2s^-1 in average at the experimental site. New analysis techniques and background suppression methods were developed. In the region of 3-8 MeV a measurement of SM cross section of (1:235+-0.577) XR_SM and Weinberg Angle of 0:264 +-0.075 which is quite consistent with the SM value of 0.23120(15)were obtained. These are the best results with wold wide level sensitivities at untested low energy region by using reactor anti-neutrinos.

APA, Harvard, Vancouver, ISO, and other styles

37

Colla, Massimiliano. "Experiments with a metastable helium atomic trap /." View thesis entry in Australian Digital Theses Program, 2006. http://thesis.anu.edu.au/public/adt-ANU20060828.104229/index.html.

Full text

APA, Harvard, Vancouver, ISO, and other styles

38

Smith, Gary Thomas. "The electron density : experimental determination and theoretical analysis." Thesis, Durham University, 1997. http://etheses.dur.ac.uk/4676/.

Full text

Abstract:

Two related lines of research in experimental electron density determination are reported in this thesis. In the first case, the well-proven and popular multipole modeling technique is applied to three high resolution, single-crystal X-ray diffraction data sets. The preliminary part of this thesis (Chapters 2-5) deals with the theoretical aspects of the multipole model, and also some of the theoretical and practical aspects of data collection and reduction. Chapter 6 reports an experimental charge density determination of a nitrogen ylide. Chapter 7 contains details of the treatment of data from a large, pendant-arm macrocyclic complex of nickel, while Chapter 8 reports the characteristics of the experimentally determined charge density for a substituted acetylene molecule which exhibits interesting intramolecular interactions. The charge densities for all three cases are analysed using Bader's Theory of Atoms in Molecules. The latter part of this thesis deals with more novel ways of treating experimental data. Chapter 9 gives a thorough review of the literature on the application of Maximum Entropy techniques to image reconstruction in general and charge density determination in particular, followed in Chapter 10 by an application to diffraction data from the cubic phase of acetylene. The novel approach of removing core scattering from the data is developed and gives improved results. Chapter 11 reviews some aspects of fermion density matrices and their relationship to electron density functions and X-ray scattering, followed in Chapter 12 by results from the density matrix refinement method applied to diffraction data from formamide. Particular emphasis is placed upon basis set effects, idempotency and various N-representable approximations to the experimentally determined density matrix.

APA, Harvard, Vancouver, ISO, and other styles

39

Mowrey, Richard Carlton. "Theoretical studies of inelastic molecule-surface and resonant electron-atom and electron-molecule scattering /." The Ohio State University, 1985. http://rave.ohiolink.edu/etdc/view?acc_num=osu148725958026243.

Full text

APA, Harvard, Vancouver, ISO, and other styles

40

Yalim, Hueseyin Ali. "Electron impact excitation of atomic hydrogen." Thesis, University of Newcastle Upon Tyne, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.388151.

Full text

APA, Harvard, Vancouver, ISO, and other styles

41

Holbrook, Owen. "Simulation of energy filtered electron microscopy." Thesis, University of Bath, 1998. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266475.

Full text

APA, Harvard, Vancouver, ISO, and other styles

42

Sang, Robert Thomas, and n/a. "Superelastic Electron Scattering from Laser Excited States of Sodium." Griffith University. School of Science, 1995. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20050921.120911.

Full text

Abstract:

This thesis presents the results of a series of experiments in which electrons are superelastically scattered from various laser excited states of sodium. The atoms, once in the optically prepared state, are forced to relax via the superelastic collision with an electron. The rate of detection of superelastically scattered electrons was measured as a function of the laser polarisation which enabled pseudo Stokes parameters to be determined. These pseudo Stokes parameters are functions of both optical pumping parameters and atomic collision parameters. The optical pumping parameters describe the laser-atom interaction and the atomic collision parameters describe the electron-atom collision process. Three different laser excitation mechanisms were used to optically pump the atoms into various excited states. The first of these used a single laser tuned to the 32S 112(F'=2 hyperfine state)-~32P312 transition. The excited atoms underwent a superelastic collision with an electron leaving the atom in the ground state and pseudo Stokes parameters were measured as a function of both scattering angle and incident electron energy. The second superelastic experiment, utilised a folded step excitation mechanism which employed two lasers tuned from the two hypethne states of the 32S112 ground state respectively to the 32P312 excited state. Power broadening effects in the single laser experiment cause the atoms to be optically pumped into the F= 1 hyperfine ground state. The laser powers used were not great enough to power broaden the hyperfine ground states and as such the F'= 1 sublevel effectively acted as a sink. The folded step excitation method enabled the excited state population to be increased so that data at larger scattering angles could be obtained. Stokes parameters from both of these experiments which had an incident energy range of 10eV to 30eV and an angular range of 5°-25° were compared to three current electron-atom scattering theories and previous experimental data. Overall, fair to good agreement was found between theory and experiments for the individual Stokes parameters. Losses of coherence was observed at small scattering angles (50.200) at 20eV and 25eV incident electron energies which were poorly modelled by the three different theories. The third superelastic experiment involved the use of two lasers of specified polarisation to stepwise excite the atoms to the 32D512 excited state. Superelastic collisions with incident electron energies of 20eV from the 32D512-*32P312~312 collision were studied at three different scattering angles and pseudo Stokes parameters for the case where the polarisations of the radiation from the lasers were parallel were measured. The single step and folded step laser-atom interactions for it excitation were modelled using a full quantum electrodynamical treatment so that the optical pumping parameters from the single and folded step experiments could be investigated. Equations of motion were derived in the Heisenberg picture and it is shown that for the single laser case 59 equations of motion are required to fully model the interaction and for the folded step ease 78 equations of motion are required. The results of calculations demonstrated that the optical pumping parameters were sensitive to laser intensity, laser detuning and the Doppler width of the atomic beam. The theoretical quantum electrodynamical calculation results were in good agreement with the experimental results.

APA, Harvard, Vancouver, ISO, and other styles

43

Hargreaves, Leigh Randall, and harg0032@flinders edu au. "Absolute Electron Scattering Cross Sections for the CF2 Radical." Flinders University. School of Chemsitry, Physics and Earth Sciences, 2008. http://catalogue.flinders.edu.au./local/adt/public/adt-SFU20080430.103821.

Full text

Abstract:

This thesis describes an experimental study of elastic electron scattering from CF2 radicals, in the intermediate energy regime. Measurements of the absolute differential, integral and momentum transfer cross sections for CF2 are presented. These measurements were performed using a new crossed beam spectrometer, incorporating a supersonic gas source and normalised using a new technique, with both of these features being extensively developed as a major part of this study. The organisation of this thesis is as follows: A brief justification for this research is presented in Chapter 1, together with a review of the spectroscopy and electron collision cross sections which are currently available for the CF2 radical. The crossed beamed apparatus and experimental techniques used to perform the present cross section measurements are then described in detail in Chapter 2, and the theory behind the new normalisation technique is subsequently presented in Chapter 3. Results from the present study are given in Chapter 4. Firstly, differential cross sections measurements for stable molecules are presented, to validate the new normalisation method. Characterisation data for the dissociation dynamics of C2F4 into CF2 radicals are then presented and, finally, differential cross section measurements for the CF2 radical are explored. Where possible, the measured data for CF2 are compared against results from theoretical calculations and the implications of the present results are discussed. The major findings of this research are then summarised in Chapter 5, and directions for future research using the present apparatus are also discussed here. Finally, some additional findings from this research and calibration data for the current apparatus are given in the appendices.

APA, Harvard, Vancouver, ISO, and other styles

44

Jillings, Christopher James. "The electron scattering reaction in the Sudbury Neutrino Observatory." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape9/PQDD_0006/NQ42947.pdf.

Full text

APA, Harvard, Vancouver, ISO, and other styles

45

Drebot, Illya. "Electron beam dynamics with and without Compton back scattering." Phd thesis, Université Paris Sud - Paris XI, 2013. http://tel.archives-ouvertes.fr/tel-00920424.

Full text

Abstract:

This thesis introduce my work on transverse and longitudinal non linear dynamics of an electron beam in ThomX, a novel X-ray source based on Compton backscattering. In this work I implemented in simulation code theoretical models to calculate transverse and longitudinal non linear dynamics under Compton back scattering. The processes studied include collective effect such as longitudinal space charge, resistive wall and coherent synchrotron radiation, intra beam scattering. I also implemented a longitudinal feedback algorithm and studied the effect of the feedback's delay in the simulation to explore its effects on beam dynamics. This code allows to perform a full 6D simulation of the beam dynamics in a ring under Compton back scattering taking into account the feedback stabilisation for the 400 000 turns (~ 20 ms) of one injection cycle. One important feature is that this simulation code can be run on a computer farm. Using this code I investigated the electrons dynamics in ThomX and the flux of scattered Compton photons. I analysed the relative contribution of each physical phenomena to the overall beam dynamics and how to mitigate their disruptive effect. As part of my work on longitudinal phase feedback I also measured and analysed properties of the ELETTRA RF cavity to be used on ThomX.

APA, Harvard, Vancouver, ISO, and other styles

46

Blais, Noël. "Modified fermi-eyges electron scattering in tissue equivalent media." Thesis, McGill University, 1990. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=70178.

Full text

Abstract:

A theoretical and experimental study of the spatial spread of electron dose distributions for pencil and broad electron beams in various media is presented. We discuss in detail two methods for measurement of electron beam kinetic energies, describe our technique for the measurement of the optical density versus dose relationship for radiographic films, and present the experimental set-up for the measurement of the spatial spread of electron dose distributions for pencil and broad electron beams.
The Fermi-Eyges theory for the small angle multiple Coulomb scattering describes the spatial electron distribution in scattering media. The spatial spread of a pencil electron beam in a phantom as predicted by the Fermi-Eyges theory is an increasing function of depth in phantom irrespective of the depth. Our experiments, on the other hand, show that the spatial spread indeed increases with depth until depths close to 2/3 of the practical electron range, but at larger depths the spatial spread saturates, then decreases and vanishes at depths greater than the range of electrons in the material. To describe the observed saturation and the decrease of the spatial spread at depths beyond 2/3 of the practical electron range we introduce an electron absorption term containing four empirical parameters into the original Fermi differential equation and show that its solution describes the experimental results obtained for pencil electron beams of various energies in polystyrene, cork and aluminum phantoms. We also compare with experimental results the spatial electron dose distributions predicted by the Fermi-Eyges theory and the modified Fermi-Eyges theory for collimated broad electron beams.

APA, Harvard, Vancouver, ISO, and other styles

47

Jensen, Erik Troels. "Low energy electron scattering studies of molecules at surfaces." Thesis, University of Cambridge, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334137.

Full text

APA, Harvard, Vancouver, ISO, and other styles

48

Harvey, Matthew. "Low Energy Electron Scattering from a Pulsed AC-MOT." Thesis, University of Manchester, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.503654.

Full text

APA, Harvard, Vancouver, ISO, and other styles

49

Lin, Shaohua. "Analysis of Electron Wave Scattering by Nano Grating Structure." Honors in the Major Thesis, University of Central Florida, 2005. http://digital.library.ucf.edu/cdm/ref/collection/ETH/id/768.

Full text

Abstract:

This item is only available in print in the UCF Libraries. If this is your Honors Thesis, you can help us make it available online for use by researchers around the world by following the instructions on the distribution consent form at http://library.ucf
Bachelors
Engineering and Computer Science
Electrical Engineering

APA, Harvard, Vancouver, ISO, and other styles

50

Carter, Paul James Anthony. "Acoustic phonon scattering by a 2 dimensional electron gas." Thesis, University of Nottingham, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.329844.

Full text

APA, Harvard, Vancouver, ISO, and other styles

We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!