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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.

Angular dependent interaction of metastable helium molecules on the surfaces of helium nanodroplets /

Petluri, Raghuram. January 2005 (has links)
Thesis (Ph. D.)--University of Rhode Island, 2005. / Typescript. Includes bibliographical references (leaves 100-108).

High resolution studies of pressure broadening

Rebbeck, M. M. January 1969 (has links)
No description available.

Theory of pure vibrational transitions of ¹⁶O₂ in solid parahydrogen.

January 2010 (has links)
Yang, Mei. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 73-75). / Abstracts in English and Chinese. / THESIS COMMITTEE --- p.II / ABSTRACT --- p.III / 中文摘要 --- p.V / ACKNOWLEDGENTS --- p.VI / TABLE OF CONTENTS --- p.VII / LIST OF FIGURES --- p.IX / LIST OF TABLES --- p.X / Chapter CHAPTER 1 --- INTRODUCTION --- p.1 / Chapter 1.1 --- Matrix isolation spectroscopy --- p.1 / Chapter 1.2 --- Properties of Molecular Hydrogen: A Review --- p.3 / Chapter 1.3 --- Unique properties of solid hydrogen --- p.8 / Chapter CHAPTER 2 --- THEORETICAL BACKGROUND --- p.12 / Chapter 2.1 --- Multipole moments of molecules --- p.12 / Chapter 2.2 --- POLARIZABILITY --- p.14 / Chapter 2.3 --- Pair intermolecular potential --- p.15 / Chapter 2.4 --- Multipole induced transitions --- p.20 / Chapter CHAPTER 3 --- THEORY OF MATRIX ISOLATED 02 IN SOLID PARAHYDROGEN --- p.24 / Chapter 3.1 --- Structural properties of 1602 --- p.24 / Chapter 3.1.1 --- Group theoretical treatment --- p.24 / Chapter 3.1.2 --- Rovibrational wavefunctions and energies --- p.26 / Chapter 3.2 --- O2 isolated in hcp crystal field of parahydrogen --- p.31 / Chapter 3.2.1 --- Group theory --- p.31 / Chapter 3.2.2 --- Crystal field splitting --- p.37 / Chapter 3.2.3 --- Effect of quadrupolar induction --- p.42 / Chapter 3.2.4 --- Pure vibrational transitions --- p.42 / Chapter 3.2.5 --- Calculation of quadrupole matrix elements --- p.47 / Chapter CHAPTER 4 --- RESULTS AND DISCUSSION --- p.54 / Chapter 4.1 --- Results --- p.55 / Chapter 4.1.1 --- Effect of quadrupolar induction --- p.55 / Chapter 4.1.2 --- Crystal field splitting of rovibrational levels of O2 in p-H2 matrix --- p.57 / Chapter 4.1.3 --- Predicted pure vibrational spectrum --- p.64 / Chapter 4.2 --- Discussion and Conclusion --- p.67 / REFERENCE --- p.73

Laser spectroscopy of caesium dimers

Butcher, Louise Sara January 1997 (has links)
We have obtained spectra of 10 vibrational bands of the Cs<sub>2</sub> (2)<sup>3</sup>∏<sub>u</sub> ← ϰ<sup>3</sup>∑<sup>+</sup><sub>9</sub> system. The molecules were formed in a supersonic free jet expansion, and were excited by light from a single mode CW dye laser. The total laser induced fluorescence was measured at 90° to the incident light and molecular beam, using a photomultiplier. Using a slit system to image a selected part of the interaction region, we have reduced the Doppler width to about 350MHz. We have been able to resolve the discrepancy between the different vibrational band positions given in two previous papers. Our vibrational bands show broad rotational contours, but we have not been able to resolve individual rotational lines. We have also obtained rotationally resolved spectra of the bandhead region of 22 vibrational bands of the Β<sup>1</sup>∏<sub>9</sub> ← X<sup>1</sup>∑<sup>+</sup><sub>u</sub> system. We found that the frequencies of the bandheads agreed with the bandhead positions deduced from the Dunham coefficients of a previous work. We have developed a theoretical model of the rotational structure and intensity distribution, taking into account optical pumping and the small solid angle subtended by the detector. By fitting this model to the experimental spectrum of the v' = 3,u∿ = 0 band using least squares optimization, we were able to extract rotational constants and line positions. We found that these line positions were in good agreement with those from the previous work. We have discussed how such spectroscopic data may be used in a determination of the s-wave scattering length of caesium, and we have reviewed the validity of the scattering length and other pararneterisations of low energy Cs-Cs interactions.

High-resolution analytical electron microscopy and creep deformation of silicon nitride ceramics /

Jin, Qiang. January 1998 (has links)
Thesis (Ph.D.) -- McMaster University, 1998. / Includes bibliographical references (leaves 186-196). Also available via World Wide Web.

High resolution spectroscopy of old stars and young disks

Bitner, Martin Allan, January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2008. / Vita. Includes bibliographical references.

High resolution infrared laser spectroscopy of CH[subscript 5 superscript +] /

White, Edmund Thomas. January 1999 (has links)
Thesis (Ph. D.)--University of Chicago, Dept. of Chemistry, August 1999. / Includes bibliographical references. Also available on the Internet.

Laser-induced fluorescence spectroscopy of the alkoxy radicals

Liu, Jinjun, January 2007 (has links)
Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 280-284).

Techniques in high resolution observations from the ground and space, and imaging of the merging environments of radio galaxies at redshift 1 to 4

Steinbring, Eric 03 August 2018 (has links)
High resolution imaging and spectroscopy are invaluable tools for extragalactic astronomy. Galaxies with redshifts of 1 or more subtend a very small angle on the sky—typically, only about an arcsecond. Unfortunately, this is also approximately the angular resolution achieved with a ground-based telescope regardless of its aperture. Atmospheric turbulence ruins the image before it reaches the telescope but the emerging technology of adaptive optics (AO) gives the observer the possibility, within limitations, of correcting for these effects. This is the case for instruments such as the Canada-France-Hawaii Telescope (CFHT) Adaptive Optics Bonnette (AOB) and the Gemini North Telescope (Gemini) Altitude-Conjugate Adaptive Optics for the Infrared (Altair) systems. The alternative is to rise above the limitations of the atmosphere entirely and put the telescope in space, for example, the Hubble Space Telescope (HST) and its successor, the Next-Generation Space Telescope (NGST). I discuss several techniques that help overcome the limitations of AO observations with existing instruments in order to make them more comparable to imaging from space. For example, effective dithering and flat-fielding techniques as well as methods to determine the effect of the instrument on the image of, say, a galaxy. The implementation of these techniques as a software package called AOTOOLS is discussed. I also discuss computer simulations of AO systems, notably the Gemini Altair instrument, in order to understand and improve them. I apply my AO image processing techniques to observations of high-redshift radio galaxies (HzRGS) with the CFHT AOB and report on deep imaging in near-infrared (NIR) bands of 6 HzRGs in the redshift range 1.1 ≤ z ≤ 3.8. The NIR is probing the restframe visible light—mature stellar populations—at these redshifts. The radio galaxy is resolved in all of these observations and its ‘clumpier’ appearance at higher redshift leads to the main result—although the sample is very small—that these galaxy environments are undergoing mergers at high redshift. Finally, I look to the future of high resolution observations and discuss simulations of imaging and spectroscopy with the NGST. The computer software NGST VI/MOS is a ‘virtual reality’ simulator of the NGST observatory providing the user with the opportunity to test real observing campaigns. / Graduate

Design of a high-efficiency, high-resolution x-ray spectrometer for 1s Lamb shift measurements

Shinpaugh, Jefferson L. January 1985 (has links)
Call number: LD2668 .T4 1985 S54 / Master of Science

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