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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

Evaluation of a four-element beta gamma personnel dosimetry badge

Tietze, Lorrie R. January 1985 (has links)
Call number: LD2668 .T4 1985 T53 / Master of Science
2

A beta dosimeter and spectrometer utilizing plastic scintillators and a large-area avalanche photodiode

Kriss, Aaron A. 03 June 2004 (has links)
The purpose of this research was to develop and test a radiation detector to perform beta dosimetry and spectroscopy. The detector utilizes plastic scintillator volumes to produce scintillation light in proportion to the amount of energy deposited in them, and a large-area avalanche photodiode to convert the light to electrical signals. Pulse processing electronics transform the electrical signals into a format useful for analysis, and various software programs are used to analyze the resulting data. The detector proved capable of measuring dose, as compared to Monte Carlo n-Particle simulations, to within about 50% or better, depending on geometry and source type. Spectroscopy results, in conjunction with MCNP-based spectral enhancement methods, proved the detector capable of recording beta spectra with endpoint energies greater than about 250 keV. The detector shows promise for further development as a portable beta detector for field use in beta-contaminated areas. / Graduation date: 2005
3

Beta-particle backscatter factors and energy-absorption scaling factors for use with dose-point kernels

Mangini, Colby D. 26 November 2012 (has links)
'Hot particle' skin dosimetry calculations are commonly performed using homogeneous dose-point kernels (DPK) in conjunction with scaling and backscatter models to account for non-homogeneous geometries. A new scaling model for determining the actual DPK for beta-particles transmitted by a high-Z source material has been developed. The model is based on a determination of the amount of mono-energetic electron absorption that occurs in a given source thickness through the use of EGSnrc (Electron Gamma Shower) Monte Carlo simulations. Integration over a particular beta spectrum provides the beta-particle DPK following self-absorption as a function of source thickness and radial depth in water, thereby accounting for spectral hardening that may occur in higher-Z materials. Beta spectra of varying spectral shapes and endpoint energies were used to test our model for select source materials with 7.42 < Z ��� 94. A new volumetric backscatter model has also been developed. This model corrects for beta-particle backscattering that occurs both in the source medium and in the atmosphere surrounding the source. Hot particle backscatter factors are constructed iteratively through selective integration of point-source backscatter factors over a given source geometry. Selection criteria are based on individual source-point positions within the source and determine which, if any, backscatter factors are used. The new scaling model and backscatter model were implemented into the DPK-based code VARSKIN 4 for extensive dose testing and verification. Verification results were compared to equivalent Monte Carlo simulations. The results demonstrate that significant improvements can be made to DPK-based models when dealing with high-Z volumetric sources in non-homogeneous geometries. / Graduation date: 2013

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