Till startsida
To content Read more about how we use cookies on gu.se

Monte Carlo calibrations of whole body counters

Identification and quantification of gamma-emitting radioactive elements in the human body can be made using a whole body counter (WBC). The Department of Radiation Physics has a laboratory equipped with two WBC systems; the low background level of the facility (0.01 μSv/h) and the high efficiency of the WBC systems enable low-activity measurements. System I consist of two large NaI(Tl) detectors in a scanning bed geometry and has been used in contamination controls and metabolic studies. System II consists of four large plastic scintillators and was designed for clinical usages, for example to quantify the natural occurrence of K-40 to determine the total body potassium (TBK). The detectors in System II are quite large and nearly gives a 3π geometry, which ensures a high efficiency but to the cost of a low energy resolution.

In the latest decade, the interest in whole body counting has been renewed as the interest in emergency preparedness for accidents or incidents involving ionizing radiation has increased. With a calibration method that is versatile and easily adaptable to a wide range of radionuclides and their distribution in the human body, the WBC systems can be used for screening and follow-up measurements after a confirmed intake of a radionuclide. Therefore, extensive work has been made to create Monte Carlo (MC) calibrations of the department’s two WBC systems. The MC model of System II, which focused on the coupled ionizing particle and optical photon transport, has been described in several articles and a Ph.D. thesis. System II was MC calibrated using the ICRP computational phantoms, which enables calibrations for wide range of radionuclides and their biokinetic distribution.

Currently, there are two on-going projects involving the WBC systems. In one project, voxel phantoms of the St. Petersburg brick phantoms, UP-02T, (a well-known WBC calibration phantom) have been made and is now validated and compared to the ICRP computational phantoms. In the other project, a MC calibration of System I is to be created and validated. Since System I is a scanning bed geometry, the calibration will include the time-dependent detector movements.

Nilsson J, Cuplov V and Isaksson M 2015 Identifying key surface parameters for optical photon transport in GEANT4/GATE simulations. Accepted for publication in Appl. Radiat. Isot.

Cartemo P, Nilsson J, Nordlund A and Isaksson M 2014 Building a generic voxel phantom of IRINA for Monte Carlo simulations. NKS report: NKS-323, ISBN 978 87 7893 404 8.

Nilsson J 2014 Modeling of Radiative Processes in Organic Scintillators Thesis for the degree of Doctor of Philosophy at the Department of Physics, University of Gothenburg, Sweden ISBN 978 91 628 8938 8. 

Nilsson J and Isaksson M 2014 A Monte Carlo calibration of a whole body counter using the ICRP computational phantoms. Radiat. Prot. Dosim. 163 458-467.

Nilsson J and Isaksson M 2014 The design of a low activity laboratory housing a whole body counter consisting of large plastic scintillators and the work towards a flexible Monte Carlo calibration. Prog. Nucl. Sci. Tech. 4 427-431.

Nilsson J 2011 Towards a flexible Monte Carlo calibration of a whole body counter spectrometer system – Highlighting the need of increased model complexity for large plastic scintillators Thesis for the degree of Licentiate of Philosophy at the Department of Physics, University of Gothenburg, Sweden ISBN 978 91 628 8296 9.

Nilsson J and Isaksson M 2010 Whole body counting with large plastic scintillators as a tool in emergency preparedness – determination of total efficiency and energy resolution. Proceedings Third European IRPA Congress Helsinki Finland ISBN 978 952 478 551 8.

Nilsson J and Isaksson M 2010 A comparison between Monte Carlo calculated and measured total efficiencies and energy resolution for large plastic scintillators used in whole body counting. Radiat. Prot. Dosim. 144 555-559.

Page Manager: Johan Spetz|Last update: 6/25/2015

The University of Gothenburg uses cookies to provide you with the best possible user experience. By continuing on this website, you approve of our use of cookies.  What are cookies?