Nuclear Technology Laboratory
Department of Electrical & Computer Engineering,
Aristotle University of Thessaloniki,
Macedonia, Greece.

Nuclear Technology Laboratory

Health Physics Society : Volume 76, Number 1, January 1999

CONTRIBUTION OF 137Cs TO THE TOTAL ABSORBED GAMMA DOSE RATE IN AIR IN A GREEK FOREST ECOSYSTEM: MEASUREMENTS AND MONTE CARLO COMPUTATIONS

A. Clouvas, S. Xanthos, M. Antonopoulos-Domis, and D. A. Alifragis

Abstract-The absorbed gamma dose rate in air 1 m above soil due to natural gamma emitters and 137Cs from the Chernobyl accident was determined inside a Quercus conferta Kit ecosystem in Northern Greece by combination of Monte Carlo simulations with the MCNP code and in-situ gamma spectrometry measurements. The total absorbed gamma dose rate in air is about 64 nGy h-1, where 40% of this value is due to 137Cs and 60% to natural gamma emitters. The Monte Carlo simulations indicated that the gamma absorbed dose rate in air due to 137Cs is mainly due (70%) to unscattered radiation and to a lesser extent (30%) to the scattered radiation. The results obtained with the Monte Carlo simulations for the unscattered radiation were in very good agreement with the experimental values deduced by in-situ gamma spectrometry measurements. From the combination of the Monte Carlo simulations and in-situ gamma spectrometry measurements a conversion factor C = 1 nGy h-1/kBq m-2 was deduced for 137Cs. This factor must be used with caution and only for forest sites similar to the one used for this work.
Full publication available in : (PDF Format)



  | Home Page | | Laboratory Profile | | Personnel | | Current Activities | | Publications | | Measurements by NTL |
| News | | Courses| | Links | | E-Mail us |