Monte Carlo calculation of dose rate conversion factors for external exposure to photon emitters in soil
The dose rate conversion factors {dot D}{sub CF} (absorbed dose rate in air per unit activity per unit of soil mass, nGy h{sup {minus}1} per Bq kg{sup {minus}1}) are calculated 1 m above ground for photon emitters of natural radionuclides uniformly distributed in the soil. Three Monte Carlo codes are used: (1) The MCNP code of Los Alamos; (2) The GEANT code of CERN; and (3) a Monte Carlo code developed in the Nuclear Technology Laboratory of the Aristotle University of Thessaloniki. The accuracy of the Monte Carlo results is tested by the comparison of the unscattered flux obtained by the three Monte Carlo codes with an independent straightforward calculation. All codes and particularly the MCNP calculate accurately the absorbed dose rate in air due to the unscattered radiation. For the total radiation (unscattered plus scattered) the {dot D}{sub CF} values calculated from the three codes are in very good agreement between them. The comparison between these results and the results deduced previously by other authors indicates a good agreement (less than 15% of difference) for photon energies above 1,500 keV. Antithetically, the agreement is not as good (difference of 20--30%) for the low energy photons.
- Research Organization:
- Aristotle Univ. of Thessaloniki (GR)
- Sponsoring Organization:
- Greek General Secretariat of Research and Technology
- OSTI ID:
- 20020651
- Journal Information:
- Health Physics, Vol. 78, Issue 3; Other Information: PBD: Mar 2000; ISSN 0017-9078
- Country of Publication:
- United States
- Language:
- English
Similar Records
Experimental comparison of the responses of CAF{sub 2} and LIF TLD chips
14-MeV Neutron Generator Used as a Thermal Neutron Source