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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.
31

Scientific application of the Santa Barbara instrument group self-guided spectrograph

Welsh, Frederick V. January 2004 (has links)
The Santa Barbara Instrument Group self-guided spectrograph is aimed primarily at the advanced amateur astronomer. This study has determined that this instrument is capable of being used for scientific research. A comparison lamp box was built to be used in conjunction with the spectrograph. A test was conducted to determine the accuracy of the grating positioning micrometer. A chart was created to allow the conversion of the micrometer readings to correlate with the position of the low-dispersion grating. To determine the scientific applicability of the spectrograph, it was used to: (1) measure the expansion rate of Nova Sagittarius 2004, (2) look for a 13.9-minute periodicity in the width and position of the H-alpha line of the binary star system X Persei, and (3) to measure the Doppler shift of X Persei. The instrument proved to be capable of being used to determine radial velocities and Doppler shifts. / Department of Physics and Astronomy
32

The development of a detector system for faint object spectroscopy on the Isaac Newton Telescope

Waltham, Nicholas Richard January 1987 (has links)
The work reported in this thesis describes the development of the CCD instrumentation for the Faint Object Spectrograph on the 2.5m Isaac Newton Telescope at the Observatorio del Roque de los Muchachos, more commonly known as the La Palma Observatory. The Faint Object Spectrograph is a highly efficient, fixed-format CCD spectrograph aimed at low resolution spectrophotometry (15-20 A FWHM) over a wide spectral range (400-1050 nm). Its high throughput, compared with that of more conventional spectrographs, is due to the small number of optical surfaces, and the minimum vignetting which results from, locating the CCD inside the spectrograph camera. A CCD camera system is described which was developed primarily to test and commission the Faint Object Spectrograph, but also to assess the characteristics of the GEC P8603 CCD used In the spectrograph, and optimize its performance for this application. The use of CCDs in astronomy is now commonplace but there still remains some uncertainty as to which aspects of their performance need to be most critically assessed when choosing a device for a particular application. It is argued that it is important to consider not only the obvious characteristics such as quantum efficiency, spectral coverage, readout noise and geometrical format, but also, and particularly at astronomically relevant low-light levels, the consequences of the more subtle properties such as charge transfer efficiency, threshold effects and chip defects. The CCD detector in the Faint Object Spectrograph is located inside the spectrograph camera and needs to be positioned to high accuracy within the optical path. A microprocessor system is described which enables the CCD detector to be aligned remotely from the observer's control console. Finally, the commissioning of the Faint Object Spectrograph on the Isaac Newton Telescope is described, and some of the first results obtained during commissioning are presented in order to illustrate its potential in the field of faint object spectroscopy.
33

The precision screw in scientific instruments of the 17th-19th centuries : with particular reference to astronomical, nautical and surveying instruments

Brooks, Randall Chapman January 1989 (has links)
Published articles have been removed from the Appendices of the electronic copy of this thesis due to third party copyright restrictions. The complete version can be consulted at the University of Leicester Library.
34

Liquid crystal devices in adaptive optics

Birch, Philip Michael January 1999 (has links)
Large aperture astronomical telescopes have a resolution that is limited by the effects of the Earth's atmosphere. The atmosphere causes incoming wavefronts to become aberrated, to correct for this adaptive optics is employed. This technique attempts to measure the incident wavefront and correct it, restoring the original image. Conventional techniques use mirrors that are deformed with piezo-electric crystals, this thesis uses an alternative technique. Two different types of liquid crystal spatial light modulators are used as the corrective elements. The advantages and disadvantages of both are assessed in an attempt to find which system is the best for astronomical adaptive optics.
35

Studies in astronomical interference spectroscopy in the balloon ultraviolet

McQuoid, J. A. January 1980 (has links)
No description available.
36

High spectral resolution studies of the atomic oxygen, 630 nm, dayglow

Cocks, Terry Douglas January 1977 (has links)
201 leaves : ill., tables, graphs ; 31 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Mawson Institute for Antarctic Research, 1977
37

Filamentary molecular clouds and their prolate cores /

Fiege, Jason D. January 1999 (has links)
Thesis (Ph. D.)--McMaster University, 1999. / Includes bibliographical references (leaves 247-252). Also available via World Wide Web.
38

High spectral resolution studies of the atomic oxygen, 630 nm, dayglow.

Cocks, Terry Douglas. January 1977 (has links) (PDF)
Thesis (Ph. D.)--University of Adelaide, Mawson Institute for Antarctic Research, 1977.
39

Ueber die anwendung der darstellenden geometrie bei figuren der astronomischen geographie ...

Dietz, Ernst, January 1907 (has links)
Inaug.-diss.--Basel. / Curriculum vitae. "Verzeichnis der bentitzten litteratur": p. [71].
40

Photometric and spectroscopic properties of void galaxies in the Sloan Digital Sky Survey /

Rojas, Randall R. January 2004 (has links)
Thesis (Ph. D.)--Drexel University, 2004. / Includes abstract and vita. Includes bibliographical references (leaves 113-124).

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