Correction factors and performance of a C sealed water calorimeter

Abstract

In the past two decades, the water calorimetry technique for determination of absorbed dose to water in several types of radiation beams has moved significantly closer to being a recognized method. In this paper we summarize the constructional details of a 4 degrees C sealed water calorimeter currently in operation at the University of Gent. This sealed water (SW) calorimeter is of the Domen type and has been improved in several aspects compared with its original design. The relevant correction factors for heat transport and for field perturbation are described. Using relative response measurements in 60Co, we experimentally verified the relative heat defect for two distinct chemical systems, using two different detection vessel arrangements. The overall 1sigma uncertainty on the absorbed dose to water at 60Co based on this system amounts to 0.7%.

Direct measurement of electron beam quality conversion factors using water calorimetry

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Air kerma and absorbed dose standards for reference dosimetry in brachytherapy

“…At this temperature, water has its maximum density, and setting the operating temperature to this value minimizes convection. 61 Perturbation correction factors were calculated with MC techniques and heat transfer simulations. A detailed uncertainty budget was presented for absorbed dose rate measurements of an HDR 192 Ir source for a source-to-detector distance of 5.5 cm.…”

Development of a water calorimetry-based standard for absorbed dose to water in HDR I192r brachytherapy

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