A calorimetric thermal neutron dosemeter

K. Haack

    Research output: Book/ReportReportResearch

    105 Downloads (Pure)


    In order to attain a prescribed silicon resistance by neutron doping, an accurate, continuous measuring dosemeter is needed. The thermal flux density pattern in the irradiation facilities of a research reactor is subject to slow as well as fast changes during an irradiation cycle, thus impeding reliable prediction of the thermal neutron dose.

    In the 5 silicon irradiation rigs in the DR 3 reactor thermal neutron dosemeters applying the calorimetric principle are used. The absorbed energy from (n, α)-reactions in a boral sample is lead through a stainless steel rod to the surroundings. The temperature drop between the rods ends is measured by a set of thermocouples. The delta temperature is proportional to the heat absorption in the boral sample and so proportional to the neutron flux density. The thermocouple signal is integrated in the instrumentation thus supplying a measure of the thermal neutron dose.

    The calorimetric dosemeter is cheap and robust. In a thermal neutron flux density of 4x1012 ncm-2s-1 the calorimeter response will decrease about 0.7% per year owing to burn-up of boron The outside dimensions of the instrument is 26ø mm x 30 mm.
    Original languageEnglish
    Place of PublicationRoskilde, Denmark
    PublisherRisø National Laboratory
    Number of pages15
    ISBN (Print)87-550-0720-1
    Publication statusPublished - 1980


    • Risø-M-2247
    • Calorimetric dosemeters
    • Crystal doping
    • Flux density
    • In core instruments
    • Irradiation capsules
    • Neutron dosimetry
    • Neutron flux
    • Silicon
    • Thermal neutrons


    Dive into the research topics of 'A calorimetric thermal neutron dosemeter'. Together they form a unique fingerprint.

    Cite this