Calculation of uncertainties on DD, DT n/γ flux at potential irradiation positions (vertical ports) and KN2 U3 by TMC code (L11) Henrik Sjöstrand

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1 Calculation of uncertainties on DD, DT n/γ flux at potential irradiation positions (vertical ports) and KN2 U3 by TMC code (L11) Henrik Sjöstrand

2 Acknowledgements Henrik Sjöstrand and JET Contributors* EUROfusion Consortium, JET, Culham Science Centre, Abingdon, OX14 3DB, UK Department of Physics and Astronomy, Uppsala University, Box 516, , Uppsala, Sweden * See the Appendix of F. Romanelli et al., Proceedings of the 25th IAEA Fusion Energy Conference 2014, Saint Petersburg, Russia

3 Neutron measurements: neutron activation systems The KN2 neutron activation system is the reference for measurement of neutron JET. Sample close to plasma activated; 115 In(n,n ) 115m In 93 Nb(n,2n) 92m Nb Activation + decay constant integrated reaction rate + activation cross-section local neutron flux + machine response (MCNP) neutron emission 3

4 Neutron activation systems and nuclear data ( E) ( E) ( ) ( ) R = σ E Φ E E R is the activations rate σ Φ a ND i.e. T a, activation cross-section = f(neutron emission, ND ), neutron flux transport nuclear data ( E) Inferred neutron emissi on = f ( σ, ND ) T a 115 In(n,n ) 115m In We need to propagate the uncertainty of σ a and ND T to R in order to infer the uncertainty of the neutron emission T 4

5 Total Monte Carlo: TMC

6 TMC Straight forward and transparent treatment of the uncertainty propagation No linearization as used in perturbation methods. Non Gaussian behavior in input and output can be 100 modelled. More complete uncertainty 40 quantification 20 - angular distributions - cross-correlation: e.g. cross sections / angular distributions K eff Pb208 LFR

7 Example TMC for 115 In(n,n )In 115m TENDL 2013 TALYS calculation normalized to IRDFF1.0; 50 files 7

8 Results: 115 In(n,n ) 115m In activation reaction One group cross-section Reaction rate 252 Cf JET DD JET DT This work TENDL2013 [mbarn] (6.6±0.7 %) 76.0 (7.4±0.7%) 37.4 (7.2±0.7 %) Gediminas et al. IRDFF (1.7 %) 76.1 (2.2 %) 37.5 (1.4 %) E.M. Zsolnay et al. IRDFFF1.0 Exp (1.4 %) - - Calc (1.7 %) TMC high uncertainties, likely due too strong E n -E n correlations. IRDFF1.0 small uncertainty (1.7%) comparing to C/E (3.6%). G. Stankunas, P. Batistoni, S. Conroy, H.Sjöstrand, Nuclear Instruments and Methods in Physics Research Section A 788, , (2015) E.M. Zsolnay, R. Capote, H.J. Nolthenius, A. Trkov, Summary Description of the New International Reactor Dosimetric and Fusion File (IRDFF release 1.0), INDC(NDS)

9 TENDL transition TENDL2013 qualitative comparisons to experimental data for determining ND-uncertainty bands TENDL2015 quantitative comparisons to experimental data based on a more consistent implementation of Bayes theorem [1] [2] [1] P. Helgesson, H.Sjöstrand et al., Combining Total Monte Carlo and Unified Monte Carlo: Bayesian nuclear data uncertainty quantification from auto-generated experimental covariances, Progress in Nuclear Energy, accepted (2016) [2] A.J. Koning, Bayesian Monte Carlo method for nuclear data evaluation The European Physical Journal A 51 (12), 1-16,

10 TMC for transport uncertainties 52 Cr, 54,56 Fe, 58,60 Ni, and 63,65 Cu, considered to have the largest impact TENDL 2015 random files processed to ACE format MCNP6 (~300 random files /isotope) transport uncertainty in the reaction rate 115 In(n,n ) 115m In (DD and DT) 93 Nb(n,2n) 92m Nb (DT) Results compared to FENDL

11 JET MCNP model 11

12 MCNP model zoom in around activation foil Intermediate port Activation foil 12

13 Results for ΔND t TENDL2015 Number of TENDL2015 files Typically Gaussian uncertainties R Indium meta stable IE (DT) 10-7 FENDL vs. TENDL (%) STD ND (%) Δ (STD ND) (%) DD - below - R ( 115 In) DD - above - R ( 115 In) DT - below - R ( 115 In) DT - above - R ( 115 In) DT - below - R ( 93 Nb) DT - above - R ( 93 Nb) DT - below - photon DT - above - photon

14 Conclusion TENDL and the TMC method has been used to: propagated uncertainty in the activation reaction 115 In(n,n ) 115m In DD and DT, TENDL2013; 7 % uncertainty (probably an over estimation) IRDFF1.0 (DD); 2 % (might be an under estimation). calculatate reaction rate uncertainty due to uncertainty in the nuclear data of the JET machine: DD: 1-2 % DT: 4 %, 115 In, 0.3 MeV Th. DT: 1 2 %, 93 Nb, 8 MeV Th. Choice of activation foil is important! TENDL2015 comprehensive covariance information; improvements possible. The effort to improve the TENDL covariance information, can increase or decrease the final uncertainty estimates. 14

15 THANK YOU FOR LISTENING Acknowledgment This work has been carried out within the framework of the EUROfusion Consortium and has received funding from the Euratom research and training programme under grant agreement No The views and opinions expressed herein do not necessarily reflect those of the European Commission. Henrik Sjöstrand, ND

16 Questions? The TMC method has been used to: propagated uncertainty in the activation reaction 115 In(n,n ) 115m In DD and DT, TENDL2013: 7 % uncertainty (probably an over estimation) IRDFF1.0 2 % (probably an under estimation). calculatate reaction rate uncertainty due to uncertainty in the nuclear data of the JET machine: DD: 1-2 %, 115 In DT: 4 %, 115 In, 0.3 MeV DT: 1 2 %, 93 Nb, 8 MeV Choice of activation foil is important! TENDL2015 comprehensive covariance information; improvements possible. The effort to improve the TENDL covariance information, can increase or decrease the final uncertainty estimates. 16

17 Results DT - TENDL2015 Row STD ND (%) Δ (STD ND) (%) STD STAT (%) Δ (STD STAT) (%) Averaged IE flux 4 cells 2,6 0,36 3,9 0,011 Indium meta stable IE 4,3 1,1 9,5 0,056 D1 fission chamber flux 3,4 0,61 6,2 0,02 D2 fission chamber flux 4,9 0,63 7,1 0,029 D3 fission chamber flux 3,5 0,67 6,7 0, (foam above IE)flux 2,8 0,18 2 0, Indium meta stable 3,2 0,43 4,8 0, (Air collumen above the cell) 3,3 0,14 0,72 0,0017 Indium meta stable 411 4,4 0,21 1,7 0, (Intermediate port) flux 3,3 0,14 0,35 0, (Big area below the IE) flux 2,9 0,12 0,2 0,00045 Indium meta stable 372 3,8 0,16 0,44 0,0013 Averaged P-IE flux 4 cells 4,2 0,84 8,1 0,034 D1 fission chamber P-flux 4,4 0,81 8,1 0,033 D2 fission chamber P-flux 5, ,047 D3 fission chamber P-flux 3,8 1,1 9,4 0,043 (foam above IE)P- flux 4,1 0,32 3,8 0, (P-flux) 3,1 0,15 1,3 0, p-flux flux 3,4 0,15 0,6 0, p-flux 3,8 0,16 0,38 0,00091 LTIS -7204:n 2,6 3,2 14 0,11 LTIS -7206:p 4,1 0,39 4,6 0,015 LTIS -7205:p 3,3 0,38 4,3 0,013 Number of TENDL2015 files R Indium meta stable IE (DT) Typically Gaussian uncertainties Preferably, STD ND > STD STAT

18 Results DD TENDL 2015 STD ND (%) Δ (STD ND) (%) STD STAT (%) Δ (STD STAT) (%) Foam above IE n-flux 1 0,22 2,1 0,0024 Foam above IE- Reaction rate Indium meta stable 1,1 0,82 4,5 0, (Air collumen above the cell) 1,1 0,067 0,76 0, Indium meta stable 2 0,16 1,9 0, (Intermediate port) n-flux 1,1 0,05 0,36 0, Indium meta stable 1,7 0,086 0,78 0, (Big area below the IE) flux 1 0,044 0,2 0, Indium meta stable 0,8 0,039 0,33 0,00032 TENDL 2012 STD ND (%) Δ (STD ND) (%) STD STAT (%) Δ (STD STAT) (%) (foam above IE)flux 0,99 0,22 2,1 0,0024 Foam above IE- Reaction rate Indium meta stable 0 0 4,5 0, (Air collumen above the cell) 1,3 0,071 0,77 0, Indium meta stable 1,1 0,18 1,9 0, (Intermediate port) flux 1,2 0,054 0,37 0, Indium meta stable 0,81 0,065 0,79 0, (Big area below the IE) flux 0,89 0,038 0,2 0, Indium meta stable 0,31 0,028 0,34 0,

19 Conclusion The TMC method has been used to study ND uncertainty in the reaction rates of the activation foils and for n, g-fluxes around the activation foils. Propagated uncertainty in the 115 In (n,n ) 115m reaction DD,TENDL2013: 7 % uncertainty (probably an over estimation) IRDFF 2 % (probably an under estimation). Reaction rate uncertainty due to uncertainty in the nuclear data of the JET machine: DD: 1-2 % DT: 3-4% Flux uncertainties intermediate port Gamma (DT): 3% Neutron (DT): 3% Neutron (DD): 1% 19

20 TENDL and TMC TENDL with cov-matrix r v a v Nuclear models: nuclear interaction -TALYS Check for covariance between all the libraries Select Best ND library Observables: CS, FY, Angular distribution Nuclear model parameters: many acceptable A large set of acceptable ND libraries Experimental data for calibration Total Monte Carlo: uncertainty propagation Simulations: Transport codes, (MCNP, FLUKA, GEANT) Applications: Shielding, activation, material damages Petter Helgesson et al. TOWARDS TRANSPARENT, REPRODUCIBLE AND JUSTIFIED NUCLEAR DATA UNCERTAINTY PROPAGATION FOR LWR APPLICATIONS σ = σ + σ obs ND stat Erwin Alhassan et al. REDUCING A PRIORI 239 Pu NUCLEAR DATA UNCERTAINTY IN THE σ keff USING A obs SET OF CRITICALITY BENCHMARKS WITH DIFFERENT NUCLEAR DATA 20 LIBRARIES