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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.
1

Lucky imaging : beyond binary stars

Staley, Timothy January 2013 (has links)
No description available.
2

Wide angle search for extrasolar planets by the transit method /

Alsubai, Khalid. January 2008 (has links)
Thesis (Ph.D.) - University of St Andrews, June 2008.
3

Charge-coupled device optimizations for astronomy.

Lesser, Michael Patrick January 1988 (has links)
In the past decade, charge-coupled devices (CCDs) have rapidly become the astronomical imaging detector of choice for the visible and near-IR spectral regions. There are, however, several problems which have greatly reduced the availability of sufficient quality CCDs to the astronomical community. These include the low blue and ultraviolet quantum efficiency of thick devices, the lack of properly thinned devices, warped imaging surfaces, interference fringing, and the small size of the detectors themselves compared to telescope focal planes. This dissertation presents methods which can be used to optimize CCDs obtained from various manufacturers for astronomical observations. A new thinning technique which produces an optically flat surface across an entire CCD is demonstrated. A mounting technique which maintains a flat and stable imaging surface for thinned devices by bonding the CCD backside against a transparent glass support substrate is also demonstrated. Bump bonding of CCDs onto a silicon support before thinning is discussed as a future mounting/thinning technique. The design of antireflection coatings for the near-UV through near-IR spectral regions is explained and demonstrated on silicon diodes, allowing quantum efficiencies as high as 90% to be obtained. The reduction of interference fringing amplitudes by as much as 70% in the red and near-IR with AR coatings is also discussed. And finally, the design of CCD focal plane mosaics using the optimization techniques presented is discussed.
4

The development of a small scale radio astronomy image synthesis array for research in radio frequency interference mitigation /

Campbell, Jacob L., January 2005 (has links) (PDF)
Thesis (M.S.)--Brigham Young University. Dept. of Electrical and Computer Engineering, 2005. / Includes bibliographical references (p. 153-156).
5

Imaging of complete samples of Z tilde 1 3C sources / Imaging of complete samples of redshift of approximately one 3C sources

Ridgway, Susan E January 1995 (has links)
Scientific symbol in title. / Thesis (Ph. D.)--University of Hawaii at Manoa, 1995. / Includes bibliographical references (leaves 118-124). / Microfiche. / xi, 124 leaves, bound ill. 29 cm
6

Applications of linear predictors in adaptive optics

Page, Kelly A. January 2005 (has links)
Thesis (Ph. D.)--University of Wyoming, 2005. / Title from PDF title page (viewed on Nov. 5, 2007). Includes bibliographical references (p. 166-170).
7

Searching for transiting extra-solar planets at optical and radio wavelengths /

Smith, Alexis Michael Sheridan. January 2009 (has links)
Thesis (Ph.D.) - University of St Andrews, November 2009.
8

Wave-front sensing for adaptive optics in astronomy : a thesis presented for the degree of Doctor of Philosophy, University of Canterbury /

Van Dam, Marcos Alejandro. January 1900 (has links)
Thesis (Ph. D.)--University of Canterbury, 2002. / Typescript (photocopy). "March 2002." Includes bibliographical references (p. 191-197). Also available via the World Wide Web.
9

Calibration of a CCD Camera and Correction of its Images

Rest, Armin 23 August 1996 (has links)
Charge-Coupled-Device (CCD) cameras have opened a new world in astronomy and other related sciences with their high quantum efficiency, stability, linearity, and easy handling. Nevertheless, there is still noise in raw CCD images and even more noise is added through the image calibration process. This makes it essential to know exactly how the calibration process impacts the noise level in the image. The properties and characteristics of the calibration frames were explored. This was done for bias frames, dark frames and flat-field frames at different temperatures and for different exposure times. At first, it seemed advantageous to scale down a dark frame from a high temperature to the temperature at which the image is taken. However, the different pixel populations have different doubling temperatures. Although the main population could be scaled down accurately, the hot pixel populations could not. A global doubling temperature cannot be used to scale down dark frames taken at one temperature to calibrate the image taken at another temperature. It was discovered that the dark count increased if the chip was exposed to light prior to measurements of the dark count. This increase, denoted as dark offset, is dependent on the time and intensity of the prior exposure of the chip to light. The dark offset decayes with a characteristic time constant of 50 seconds. The cause might be due to storage effects within chip. It was found that the standard procedures for image calibration did not always generate the best and fastest way to process an image with a high signal-to-noise ratio. This was shown for both master dark frames and master flat-field frames. In a real world example, possible night sessions using master frame calibration are explained. Three sessions are discussed in detail concerning the trade-offs in imaging time, memory requirements, calibration time, and noise level. An efficient method for obtaining a noise map of an image was developed, i.e., a method for determining how accurate single pixel values are, by approximating the noise in several different cases.
10

Observations of starburst galaxies science and supporting technology /

Laag, Edward Aric. January 2009 (has links)
Thesis (Ph. D.)--University of California, Riverside, 2009. / Includes abstract. Available via ProQuest Digital Dissertations. Title from first page of PDF file (viewed March 16, 2010). Includes bibliographical references. Also issued in print.

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