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Unit of absorbed dose to water

Working Group 6.23


Absorbed dose to water, Dw, is the fundamental quantity in the dosimetry for radiation therapy. The unit of absorbed dose to water is the Gray (1 Gy = 1 J/kg). By measuring the radiation-induced temperature rise in water, Dw can be realized most directly and with low uncertainties for a variety of therapeutically relevant radiation species and radiation conditions. The working group 6.23 operates and develops divers water calorimeters for this purpose.

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  • Absolute determination of absorbed dose to water for therapeutically relevant radiation types and radiation conditions:

    • for high-energy photon and electron radiation (kQ determination of ionization chambers)
    • for medium energy X-rays (70 kV - 280 kV)
    • for HDR brachytherapy sources
    • for hadron radiation (cooperation with DKFZ/HIT Heidelberg: PhD and master projects)

  • Research and development in the field of water calorimetry

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