activation calculations-present and future

Activation Calculations-Present and Future

SATIF-10June 2-4, 2010Franz Gallmeier

2 Managed by UT-Battellefor the U.S. Department of Energy CERN - SATIF-2010

The first SNS Spent Target leaving the SNS Site

target modulee

liner

TN-RAMcask


Target Activation(1)

Target

Moderators

Inner Reflector

Outer Reflector

protons

Thomas/Stevenson: Asat≈E(GeV) Bq per proton/second ASNS= 6e15 Bq


Target Activation (2) time after shutdown

nuclide

halflife (s)

shutdown 1 day 7 days 30 days 60 days 90 days 120 days 1 year 3 years 10 years

H 3 3.89E+08 3.13E+01 3.13E+01 3.12E+01 3.11E+01 3.10E+01 3.08E+01 3.07E+01 2.96E+01 2.64E+01 1.78E+01 Be 7 4.61E+06 1.78E+00 1.76E+00 1.63E+00 1.21E+00 8.17E-01 5.53E-01 3.74E-01 1.54E-02 1.16E-06 4.19E-21 Be 10 4.77E+13 4.87E-07 4.87E-07 4.87E-07 4.87E-07 4.87E-07 4.87E-07 4.87E-07 4.87E-07 4.87E-07 4.87E-07 C 14 1.80E+11 4.20E-05 4.20E-05 4.20E-05 4.20E-05 4.20E-05 4.20E-05 4.20E-05 4.20E-05 4.20E-05 4.19E-05 F 18 6.59E+03 9.44E+00 1.06E-03 2.15E-27 3.20E-118 1.08E-236 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 Na 22 8.21E+07 4.53E+00 4.52E+00 4.50E+00 4.43E+00 4.33E+00 4.24E+00 4.15E+00 3.47E+00 2.04E+00 3.15E-01 Mg 28 7.53E+04 3.98E-01 1.80E-01 1.52E-03 1.73E-11 7.49E-22 3.25E-32 1.41E-42 2.72E-127 0.00E+00 0.00E+00 Al 26 2.27E+13 2.53E-05 2.53E-05 2.53E-05 2.53E-05 2.53E-05 2.53E-05 2.53E-05 2.53E-05 2.53E-05 2.53E-05 Al 28 1.34E+02 1.55E+02 1.80E-01 1.52E-03 1.73E-11 7.50E-22 3.25E-32 1.41E-42 2.72E-127 0.00E+00 0.00E+00 Si 31 9.44E+03 3.55E+01 6.23E-02 1.82E-18 7.53E-82 1.60E-164 3.39E-247 0.00E+00 0.00E+00 0.00E+00 0.00E+00 Si 32 4.17E+09 6.60E-03 6.60E-03 6.60E-03 6.60E-03 6.60E-03 6.60E-03 6.59E-03 6.57E-03 6.50E-03 6.27E-03

• Detailed listing of radionuclide inventory by

required for realistic beam conditions.• We are close to the activity limit of the transport

cask and of the disposal site. We need good tools to predict activation related

quantities.


What do we calculate?

mkmk

kmmmm tNYtNdt

tdN

)()(

)(

Decay constants

mamm

mkmkmk

Material compositionFlux

Activation cross sections Isotope production/destruction from event generators


Tools for Activation Analyses

• Transport codes• Activation codes


Modular Approach

Particle Tracking

by Event Generator

Inelastic Reactions

by Cross Sections

Particle emissionn,β-,β+,γ,α

Tra

nspo

rt c

ode

Fluxesn,p,d,t,He-3,α,γ Residual Production Materials

Act

ivat

ion

Ana

lysi

s

Irradiation History

Decay database

Activation Cross Sections

Decay Spectra:n,β-,β+,γ,αRadionuclide Inventory by time


All-In-One-Code Approach

Particle Tracking

by Event Generator

Inelastic Reactions

by Cross Sections

Residual Nucleus

Decay

StableUnstable

Particle emissionn,β-,β+,γ,α

Tra

nspo

rt c

ode


Comparison of Approaches

All-in-one-code Modular

Pros •Decay emissions at reaction-site or position of tracked decaying ion•Proper analysis of statistical errors•Conservation of correlations on per particle basis

•Deterministic analysis gives full inventories•Allows for material depletion•Decay source terms for subsequent analyses

Cons •Large memory footprint •No statistical errors•Lost correlations•Region averaged decay sources


FLUKA-2008 (Ferrari, Fasso, Sala …)

• Reaction models: Gribov-Glauber, GINC, PE, evaporation, …• Multigroup low-energy neutron transport• Radionuclide formation:

– For many materials, but not for all, group-dependent information on the residual nuclei produced by low-energy neutron interactions is available in the FLUKA libraries. This information can be used to score residual nuclei, but it is important that the user check its availability before requesting scoring.

– Fission fragments are sampled separately, using evaluated data extracted from European, American and Japanese databases.

• Scoring of decay radiation, and residual nuclei– for requested decay time step– semi-analog


MCNPX_2.6.0 (McKinney, Hendricks …)

• Reaction models: CEM-03, LAQGSM, INCL,Isabel, Bertini, MPM, ABLA, EVAP …• Continuous energy cross section based low-energy neutron and proton transport• The depletion/burnup capability for reactor applications is implemented based on

CINDER90, and MONTEBURNS. • Charged ions from neutron capture:“neutron capture ion algorithm”: He-3, Li-6, B-10• MCNPX enables the automated calculation of delayed-gamma signatures emitted due to

– the decay of radioactive fission products created by neutron fission or photofission, – residual nuclides created by simple multi-particle interactions (SMRs).

The delayed-gamma capability uses CINDER90. Execution of the delayed gamma capability is limited to fixed sources (SDEF) and

surface sources (SSW, SSR). • Residual nuclei (from event generators only) are tallied:

– By region thru history tape and post-processing with HTAPE3 utility– Overall thru tally f8:n +ft res– With heavy-ion transport with f4:# +ft4 res zzaaa1 zzaaa2 …


The MCNPX Approach to more detailed Information

• A multitude of tasks of preparing and performing activation analyses

• Activation script does a complete activation calculation (multi-cell) with one user supplied input file minimizing the information needed

• Gamma Source Script prepares MCNPX source deck from decay gamma sources

MCNPX

Activation Script:read material compositionread fluxes E < 20/25 MeV

prepare/read H-E production anddestruction rates

mcnpx_inp

outp histp

CINDER’90 ORIHET-3 SP-FISPACT

activation_inp

Cinder90_out Orihet3_out Fispact_out

Gamma Source Script:cell identities and volumes

gamma spectra

gamma_source_inp MCNPX_sdef

MCNPX

dose rates

mcnpx_inp

MCNPX

Activation Script:read material compositionread fluxes E < 20/25 MeV

prepare/read H-E production anddestruction rates

mcnpx_inp

outp histp

CINDER’90 ORIHET-3 SP-FISPACT

activation_inp

Cinder90_out Orihet3_out Fispact_out

Gamma Source Script:cell identities and volumes

gamma spectra

gamma_source_inp MCNPX_sdef

MCNPX

dose rates

mcnpx_inp


GEANT4

Reaction models: Parton-String, G4Bertini, G4BinaryCascade, Abration-Ablation, INCL4.2+ABLA3, PC, Evaproation …

Continuous-energy low-E neutron transportRadioactive Decay - The radioactive decay module G4RadioactiveDecay and

associated classes are used to simulate the decay of radioactive nuclei by α, β+, and β¡ emission and by electron capture (EC).

The simulation model is empirical and data-driven, and uses the Evaluated Nuclear Structure Data File (ENSDF) for information on: nuclear half-lives, nuclear level structure for the parent or daughter nuclide, decay branching ratios, and the energy of the decay process.

If the daughter of a nuclear decay is an excited isomer, its prompt nuclear de-excitation is treated using the G4PhotoEvaporation class.

Sampling:Sampling of the β-spectrum, which includes the coordinated energies and

momenta of the β, ν, and residual nucleus, is performed either from histogrammed data, or through a three-body decay algorithm.

The manual did not tell me, if GEANT4 considers radionuclide production in high-precision low-energy neutron processes.


MARS15 (Mokhov, Rakhno, James …)

Reaction model: Inclusive phenomenological model, DPMJET3, CEM03, LAQGSM

MCNP low-E neutron transportBesides the straight forward

approach of following the radionuclide production in the spallation and neutron-induced activation, MARS offers an approximate solution to activation problems -the ω-factor approach – to arrive at residual dose rates.

ω-factors correlate residual dose-rates to star-densities (reaction rates above 20 MeV).

This does not work for calculating radionuclide information.

Curtesy: M. Huhtinen, CERN/TIS-RP/IR/98-28 (1998).


PHITS (Niita, Iwase …)

JAM, JQMD, Bertini


CINDER (Holloway, Wilson …)

CINDER90 released version:• Solves coupled buildup- and decay equations • Considers material destruction in balance equations• Database contains decay data and activation cross sections,

decay gamma spectra for 3400 isotopes • Neutron activation cross sections in 63 energy groups up to

20 MeV• Decay gamma structure fixed to 25 groups• Tabulating of CINDER90 results with TABCODE• Merging of results of different CINDER90 calculations by

ALLCODE

Towards CINDER-2008 package:• Improvement of mathematical algorithms• Update neutron activation cross sections (ENDF/B-VII, JEFF-

3x, JENDL) in 65 group structure• Update of decay database to 4113 nuclides (ENDF/B-VII.0,

EAF-2007, JEFF-3.11)• Photonuclear library in preparation


DCHAIN-SP 2001 (Kai, Maekawa, Kosako, Kasugai, Takada, Ikeda)

Present Version:• Developed from DCHAIN-2 code at JAEA • Decay library with 3139 nuclides, EAF-3.1, FENDL/D-2, ENSDF• Neutron activation cross sections in 175 groups from FENDL/A-2,

JENDL-AC96, JENDL-3.3• Decay Gamma lines from ENSDF, one line per nuclide (averaged

gamma energy)• Revised 65 partial activation cross sections to match better

experimental dataUpdates underway:• Improved neutron activation cross sections from JEFF-3.1A in

1968 groups improves contributions from resonance region


EASY-2007 (Forrest, Kopecky, Sublet)

EASY-2007 is the activation package of the fusion community.• Includes FISPACT-2007 activation code,• Uses EAF-2007 decay data (2233 nuclides) and cross

sections(n,p,d) for 800+ nuclides to 60 MeV• Package provides multi-group cross section libraries in various

group structures (69-351)and collapsed with flat, fission, and fusion spectra

• FISPACT-2007 can give uncertainties due to cross sections and decay constants (not yet due to input flux statistical errors)

• Contains the SAFEPAQ-II tool for processing and evaluating activation cross sections

Updates:• EAF-2010 libraries on the way• Heard rumors that FISPACT-2010 may be able to handle user-

provided radionuclide production rates extension to spallation products.


ORIHET3 (Atchison, Schaal - no longer developed)

• Decay databases:– NUBASEX built from NUBASE 3738 nuclides and uses more

than 40 decay modes – Original ORIHET data for 2456 nuclides and recognises 7

decay modes • Gamma library:

Darmstadt Gamma-ray atlas: 30752 gamma lines and intensities for 1275 nuclides

• No beta library• Requires radionuclide production rates as input


Other Activation Tools

• ALARA (Paul Wilson, U. Wisconsin)• DeTra (Aarnio, CERN)• …


Activation Data

• Decay databases• Activation cross section libraries


Decay Databases

Database Number of isotopes

Origin of data

ENDF/B-VII 3838 ENSDF, Nuclear Wallet Cards

EAF-2010(includes spin and uncertainties)

2233 ENSDF, NUBASE, JEF2.2, JEFF-3.1.1, Browne and Firestone, Nuclear Wallet Cards

JEFF-3.1.1 3852 NUBASE, ENSDF, LNHB, UKHEDD-2.x, UKPADD-6.x


High-energy Neutron Induced Activation Cross Section Databases

Library Number of Isotopes

Z Range Upper Energy

EAF-2007 816 1-100 60 MeV

JENDL/HE-2007 106 1-95 3 GeV

JEFF-3.1/A 774 1-100 20 MeV

MENDL-2 505 13-84 100 MeV

TENDL-2009 2375 6-110 200 MeV

IEAF-2009 682 1-84 1 GeV


High-energy Proton Induced Activation Cross Section Databases

Library Number of Isotopes

Z Range Upper Energy

EAF-2007 810 1-100 60 MeV

PADF-2007 2355 12-88 150 MeV

JENDL/HE-2007 106 1-95 3 GeV

JEFF-3.1 26 20-83 200 MeV

TENDL-2009 2375 6-110 200 MeV

HEPAD-2008 682 1-84 1 GeV


High-energy Activation Cross Section Databases

Library Incident Particles

Procedure of Generation

PADF-2007 p TALYS, ALICE/ASH, EXFOR

HEAD-2009 (IEAF-2009+HEPAD-2009)

p,n (Bertini,Isabel,INCL)*(Dresner,ABLA)CASCADE, CEM03, EXFOR global

TENDL-2009 p,n,d,t,he3,α TALYS (default and adjusted)Validated for integral isotope prod. xs

EAF-2007 p,n,d EXFOR+TALYS+IEAF+ALICE…evaluated

JENDL/HE-2007 p,n ENDF/B-6+GNASH+ALICE-F +JAM/GEM+JQMD/GEM

JEFF-3.1 p,n For neutrons EAF-2003 reformattedFor protons TALYS


Benchmarking

• Microscopic benchmarking – of Spallation Models (CEM, INCL, JAM, CASCADE, QMD,

DPMJET, …)– Precompound nuclear reaction models

• Macroscopic benchmarking – through application type quanitities (decay heat, residual

dose rates, foil activation)– Measured integral production cross sections


IAEA Spallation Physics Benchmark – Radionuclide Production

Isotope distributions by inverse kinematic experiments

Mass and Charge distributions by inverse kinematic experiments


Examples: Mass Production


Uncertainty in activation cross-section calculations –A. Yu. Konobeyev et al., Kerntechnik 73, 2008

(p,x) E=0-150MeV


Benchmarking of isotope production in mixed energy and mixed particle fields

• Typically libraries like EAF and TENDL are validated to a collection of experimental integral production cross sections– J. Kopecky, VALIDATION OF TENDL2009 USING INTEGRAL

MEASUREMENTS,JUKO Research, EAFDoc54, Feb 2010

– RA Forrest et al., Validation of EASY-2007 using integral measurements, UKAEA FUS 547, EURATOM/UKAEA Fusion, April 2008

• Many other examples in proceedings of SATIF-x, ARIA2008, AccApp’xx, ICRS-xx, …


How to improve Activation Analyses?

• Continue improving reaction models and benchmarking• make use of cross section data bases extended to

intermediate-energy• multi-group formalism and its limitations need to be

addressed• Waiting for gamma-activation cross section library• Uncertainty analysis is in development in FISPACT, can

it be adopted in other activation codes? Correct formalism needs bulky covariance matrices.

activation calculations-present and future

Documents

department of energycern

event generators

activation related quantities

transport cask

transport codefluxesn

sns site

asategev bq

6e15 bq