Sökning: "Gamma spectrometry"

Visar resultat 1 - 5 av 31 avhandlingar innehållade orden Gamma spectrometry.

  1. 1. Optimisation of environmental gamma spectrometry using Monte Carlo methods

    Författare :Francisco Javier Hernández Suárez; Peter Appleby; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; Gamma spectrometry; Environmental multitracers; Monte Carlo simulations; HPGe detectors; Efficiency calibration; Self-absorption corrections.; Fysik; Physics; Fysik; Fysik; Physics;

    Sammanfattning : Dissertation in Environmental Physics to be publicly examined in Häggsalen (Ångström Laboratory), Uppsala University, on Friday, November 8, 2002 at 10:00 am for the degree of doctor of philosophy in Physics. The examination will be conducted in English. LÄS MER

  3. 2. On-line Mobile in situ Gamma Spectrometry

    Författare :Thomas Hjerpe; Lund Medicinsk strålningsfysik; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; radiobiologi; Kärnfysik; Nuclear physics; radiation protection.; 137Cs; peak-to-valley method; depth distribution; orphan source search; orphan sources; emergency preparedness; mobile gamma spectrometry; nuclear accidents; Nuclear medicine; radiobiology; Nukleärmedicin;

    Sammanfattning : Mobile in situ gamma spectrometry is an important instrument in the emergency preparedness for nuclear accidents. This work contributes through the development of strategies and analysis methods for two applications: an on-line search for gamma-emitting orphan sources and on-line estimation of the depth distribution of 137Cs. LÄS MER

  4. 3. Improving accuracy of in situ gamma-ray spectrometry

    Författare :Jonas Boson; Christer Samuelsson; Umeå universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; gamma-ray spectrometry; in situ measurement; HPGe detector; 137Cs; Monte Carlo; efficiency calibration; measurement uncertainty; Radiological physics; Radiofysik;

    Sammanfattning : Gamma-ray spectrometry measurements performed on site, or “in situ”, is a widely used and powerful method that can be employed both to identify and quantify ground deposited radionuclides. The purpose of this thesis is to improve the calibration of high purity germanium (HPGe) detectors for in situ measurements, and calculate the combined uncertainty and potential systematic effects. LÄS MER

  5. 4. Orphan source detection in mobile gamma-ray spectrometry - Improved techniques for background assessment

    Författare :Peder Kock; Malmö Medicinsk strålningsfysik; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Gamma spectrometry; airborne; car-borne; radioactive; orphan sources; hypothesis testing; background radiation;

    Sammanfattning : Hazardous radioactive sources out of regulatory control are referred to as orphan sources. Focussing on gamma-emitting orphan sources, this thesis describes methods that can be used in mobile gamma-ray spectrometry to perform real-time discrimination between an actual source signal and the signal due to the natural radiation background. LÄS MER

  7. 5. Assessment of mobile radiometry data in radiological emergencies using Bayesian statistical methods

    Författare :Antanas Bukartas; Malmö Medicinsk strålningsfysik; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Mobile gamma spectrometry; Gamma spectrometry; Orphan source; lost source; Ionizing radiation; Bayesian; Activity; position; activity density; reconstruction; UAV; car-borne;

    Sammanfattning : Nuclear technology and the use of radiation sources have been extensively adopted in the modern world. Despite that, a number of radiological accidents, significantly affecting population and the environment, has happened. Few of the most known are accidents in Chernobyl and Fukushima nuclear power plants. LÄS MER