4th International Summer School« Nuclear Physics Methods and Accelerators in Biology and Medicine »

Monte-Carlo simulations :FLUKA vs. MCNPX

Maxime ODEN – École des Mines de Nantes (France)

Spectroscopy dpt., Nuclear Physics Institute of ASCR

Antonín Krása, Mitja Majerle, Ondřej Svoboda, Vladimír Wagner

for the Energy plus Transmutation Energy plus Transmutation collaboration

Introduction Experiments are carried out at JINR to study

spallation

p + Pb => spallation reaction

Detection of neutron with to activation detectors (Au, Al, Bi).

Activation foils activities are measured thanks to a germanium detector.

Maxime ODEN - École des Mines de Nantes - Nuclear Physics Institute of ASCR

Phasotron experiment - bare Pb target

Lead targetBeam : proton 660 MeV

Energy plus Transmutation Set-up

Maxime ODEN - École des Mines de Nantes - Nuclear Physics Institute of ASCR

• target: Pb (28.66 kg) • blanket: U (206.4 kg)• shielding: Cd + (CH2)n

Beam :

proton 0.7/1/ 1.5 /2 GeV

deuteron 1.6 / 2.52 GeV

Energy plus Transmutation Set-up

MCNPX Simulation

The obtained experimental data are used to check prediction from MCNPX (a computer simulation code based on Monte Carlo method)

MCNPX can calculate neutrons fluence where the detectors are set up

Neutron fluence multiplied by cross-sections for activation reaction give simulated activation results

Results compared to experimental results show discrepancies at higher energies (1.5 GeV and 2 GeV)

MCNPX Simulation Ratio between experiment and MCNPX

simulation results :

0

1

2

3

4

5

0 5 10 15

Radial distance [cm]

Bex

p/B

sim

Au-196Au-194Au-193Au-192Au-191

FLUKA Simulation

Verify experiments with FLUKA code: Spectrum in phasotron experiment Reaction rate in radial detectors

Two ways to calculate activation results: Multiplication with cross-sections RESNUCLEi function

FLUKA Simulation neutrons fluence Phasotron experiment with proton beam (660MeV)

MCNPX

FLUKA

FLUKA SimulationEnergy plus Transmutation

Front view Side view

Radial detectors(gold foils)

1,0

2,0

3,0

4,0

5,0

2,5 4,5 6,5 8,5 10,5 12,5

Au-196Au-194Au-193Au-192Au-191

FLUKA Simulation Ratio between experiment and FLUKA simulation results (manual

mutliplication):

ratio

Radial distance (cm)

1,0

2,0

3,0

4,0

5,0

6,0

7,0

2 4 6 8 10 12 14

Au-196Au-194Au-193Au-192Au-191

FLUKA Simulation II Ratio between experiment and FLUKA simulation results with

RESNUCLEi scoring card:

ratio

Radial distance (cm)

Conclusion FLUKA results checked by comparison with

MNCPX

FLUKA and MCNPX are expected to give similar results

Maxime ODEN - École des Mines de Nantes - Nuclear Physics Institute of ASCR

Thank you for your attention