SUITABILITY OF PORTABLE RADIONUCLIDE IDENTIFIERS FOR EMERGENCY INCORPORATION MONITORING.

The suitability of portable nuclide inspectors for incorporation measurements were tested with three probes (LaBr3(Ce), NaI(Tl) and HPGe) differing in sensitive volume and energy resolution. The efficiencies for the measurement of whole-body and lung radionuclide burden were calibrated using a whole-body block phantom with traceable radionuclide sources of 60Co, 133Ba, 137Cs, 152Eu and 40K. A standing geometry was chosen as it allows rapid positioning of persons for the measurements.

COMPARISON OF DIFFERENT PADC MATERIALS AND ETCHING CONDITIONS FOR FAST NEUTRON DOSIMETRY.

Etched-track polyallyl diglycol carbonate (PADC) dosemeters have been in use at the Paul Scherrer Institute since 1998 in neutron dosimetry for individual monitoring. In the last years, the availability of PADC materials from different manufacturers has grown, and different etching conditions were proposed, with the intention to improve the quality and overall performance of PADC in individual neutron monitoring. The goal of the present study was to compare the performance of different PADC materials and to investigate the influence of different etching conditions on sensitivity to fast neutrons and lower detection limit.

STABILITY OF THE NEUTRON DOSE DETERMINATION ALGORITHM FOR PERSONAL NEUTRON DOSEMETERS AT DIFFERENT RADON GAS EXPOSURES.

Since 2008 the Paul Scherrer Institute (PSI) has been using a microscope-based automatic scanning system for assessing personal neutron doses with a dosemeter based on PADC. This scanning system, known as TASLImage, includes a comprehensive characterisation of tracks. The distributions of several specific track characteristics such as size, shape and optical density are compared with a reference set to discriminate tracks of alpha particles and non-track background.

Measurements of the neutron dose equivalent for various radiation qualities, treatment machines and delivery techniques in radiation therapy.

In radiation therapy, high energy photon and proton beams cause the production of secondary neutrons. This leads to an unwanted dose contribution, which can be considerable for tissues outside of the target volume regarding the long term health of cancer patients. Due to the high biological effectiveness of neutrons in regards to cancer induction, small neutron doses can be important.

Monte Carlo simulation of a whole-body counter using IGOR phantoms.

Whole-body counting is a technique of choice for assessing the intake of gamma-emitting radionuclides. An appropriate calibration is necessary, which is done either by experimental measurement or by Monte Carlo (MC) calculation. The aim of this work was to validate a MC model for calibrating whole-body counters (WBCs) by comparing the results of computations with measurements performed on an anthropomorphic phantom and to investigate the effect of a change in phantom's position on the WBC counting sensitivity.