DCC comparison between Doses3D and EDEN

Transcription

1 Effect of heterogeneous distribution of radionuclides in sediment on dose rate to wildlife 234Th in canadian sediments from Saskatchewan DCC comparison between Doses3D and EDEN K. Beaugelin-Seiller / IRSN A. Hosseini / NRPA

2 DOSES3D vs EDEN DCC -µgy/h per Bq/m 2 or Bq/kg) 1.00E E E E E E E E E E-08 July results DCC Th-234 EDEN DCC Th-234 DOSES3D DCC Pa-234M EDEN DCC Pa-234M DOSES3D 1.00E Agreed scenarios More or less agreement on volume DCC -> energies checking?

3 DOSES3D vs EDEN Considering γ radiation only for EDEN results as done for Doses 3D results 1.00E E+00 July results 1.00E E+00 today DCC -µgy/h per Bq/m 2 or Bq/kg) 1.00E E E E E E E-07 DCC Th-234 EDEN DCC Th-234 DOSES3D DCC Pa-234M EDEN DCC Pa-234M DOSES3D DCC -µgy/h per Bq/m 2 or Bq/kg) 1.00E E E E E E E-07 DCC Th-234 EDEN DCC Th-234 DOSES3D DCC Pa-234M EDEN DCC Pa-234M DOSES3D 1.00E E E E Better agreement, especially for volume/mass DCCs surface DCCs???

4 DOSES3D vs EDEN Nuclear data comparison ( 234 Th gamma energies) Doses3D (ICRP38) Main energies EDEN (JEFF NEA/OCDE) MeV Yield (Bq-s) -1 MeV intensity MeV Nucleonica Emission Probability, E.P. 2.00E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E-05

5 EDEN internal checking Conversion Mev/(g.s) into Gy/d 1 MeV = J 1 g = 10-3 kg 1 j = s 1 Gy = 1 J.kg MeV J J 5 = = = g.s 3 1 kg d 10 kg. d Gy d Gy = d MeV g.s

6 EDEN internal consistency Alpha radiation 1.4E E E-02 Energy deposit ((MeV/g)/bq.s) 8.0E E-03 Surface Volume 10-3 Volume E E E E (MeV)

7 EDEN internal consistency Beta radiation Energy deposit ((MeV/g)/bq.s) 2.5E E-03 Deposit maps 1.5E E E-04 Surface Volume E E (MeV) Energy deposit ((MeV/g)/bq.s) 2.0E-03 Statisitical approach 1.5E E-03 Surface Volume E E E (MeV)

8 EDEN internal consistency Gamma radiation Energy deposit ((MeV/g)/bq.s) 2.50E E E E-06 Surface Volume (10-3) 5.00E E E (MeV) the continuity between volume and surface exposure has been proved in terms of energy deposit

9 EDEN VS MCNP Organism Radiative media (surfac or volume exposure) Exposure scene Beta radiation Gamma radiation DCC ((MeV/g).cm2/(bq/.s)) 6.0E-02 DCC ((MeV/g).cm2/(bq/.s)) 1.2E E E E E E-02 MCNP EDEN 8.0E E E-02 MCNP EDEN 1.0E E E E (MeV) 0.0E E (MeV) Work in progress: unit conversion checking (MeV/g).cm²/(Bq/s) into (MeV/g).m²/(Bq/s)

10 Methodology We have adopted the methodology developed by Valeri Taranenko in connection with FASSET (Deliverable 3 and Taranenko et al., 2004). Collate information on the principal gamma emission lines and yields of the radionuclide of interest Collate planar DCC data for the organism of interest Select the nearest energy, as FASSET reports for a limited range of energies, e.g. Th-234 has a characteristic photon emission at 63.3 kev, in FASSET the nearest DCC of 70 kev was selected Summing up and then converting to the desired unit (µgy per photon/m2 to µgy s-1 per Bq/m2 V. Taranenko, G Pr ohl and J M G omez-ros (2004). Absorbed dose rate conversion coefficients for reference terrestrial biota for external photon and internal exposures. J. Radiol. Prot. 24 (2004) A35 A62

11 An example: Th-234 MeV DCC - µgy per photon/m 2 (for MeV) Yield (Bq-s) -1 µgy s -1 per Bq/m E E 10 (0.07) 3.81E-02 6,858E E E 10 (0.07) 1.13E-01 2,034E E E 10 (0.1) 2.78E-02 6,672E E E 10 (0.1) 2.73E-02 6,552E E E 10 (0.1) 2.69E-02 6,456E-12 TOTAL = 4,6878E-11

12 Results and comparison Th-234, DCC (µgy/h per Bq/m 2 ) Configuration Organism FASSET Doses3D On surface Woodlouse 1.7E E-08 In depth (5 cm) Woodlous 5.8E E-09 On surface Insect larvae 3.6E-08 In depth (5 cm) Insect larvea 6.4E-09