rdf-syntax-grammar
mods:
  schema location: http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
  title info:
    title: Design, construction and implementation of spherical tissue equivalent proportional counter
  name:
    name part: Perez Nunez, Delia.
    role:
      role term: creator
  name:
    name part: Braby, Leslie A.
    role:
      role term: thesis advisor.
  name:
    name part: Ford, John R.
    role:
      role term: thesis advisor.
  type of resource: text
  genre: bibliography
  origin info:
    place:
      place term: txu
    date issued: 2011
    issuance: monographic
  language:
    language term: eng
  physical description:
    form: remote
    extent: 1 online resource.
  abstract: Tissue equivalent proportional counters (TEPC) are used for medical and space activities whenever a combination of high and low LET (lineal energy transfer) radiations are present. With the frequency and duration of space activities increasing, exposure to fast heavy ions from galactic cosmic radiation and solar events is a major concern. The optimum detector geometry is spherical; to obtain an isotropic response, but simple spherical detectors have the disadvantage of a non-uniform electric field. In order to achieve a uniform electric field along the detector axis, spherical tissue equivalent proportional counters have been designed with different structures to modify the electric field. Some detectors use a cylindrical coil that is coaxial with the anode, but they are not reliable because of their sensitivity to microphonic noise and insufficient mechanical strength. In this work a new spherical TEPC was developed. The approach used was to divide the cathode in several rings with different thicknesses, and adjust the potential difference between each ring and the anode to produce an electric field that is nearly constant along the length of the anode. A-150 tissue equivalent plastic is used for the detector walls, the insulator material between the cathode rings is low density polyethylene, and the gas inside the detector is propane. The detector, along with the charge sensitive preamplifier, is encased in a stainless steel vacuum chamber. The gas gain was found to be 497.5 at 782 volts and the response to neutrons as a function of angle was constant ±7%. This spherical tissue equivalent proportional counter detector system will improve the accuracy of dosimetry in space, and as a result improve radiation safety for astronauts.
  note: by Delia Perez Nunez.
  note: "Major Subject: Nuclear Engineering"
  note: Title from author supplied metadata (automated record created 2011-08-09 15:09:44).
  note: Electronic resource.
  note: Doctor of Philosophy Texas A&M University 2008 http://hdl.handle.net/1969.1/ETD-TAMU-2789
  note: Includes bibliographical references.
  note: Text (Dissertation)
  subject:
    topic: Major nuclear engineering
  subject:
    topic: Space Radiation
  subject:
    topic: Spherical TEPC
  subject:
    topic: Neutron Dosimetry
  identifier: http://hdl.handle.net/1969.1/ETD-TAMU-2789
  record info:
    record content source: TXA
    record creation date: 110819
    record change date: 20151202142330.0
    record identifier: in00002708392