Transcript Document

Cosmogenic induced activity
IDEA (Integrated Double-beta decay European Activities)
Task leaders: Maura Pavan, Susana Cebrián
Susana Cebrián
Universidad de Zaragoza / Università di Milano-Bicocca
Heidelberg, 21st-22nd October 2004
Presentation
 “Cosmogenic induced activity” is the Work Package 4 of JRA2 / IDEA in
ILIAS, in connection with:
Task 2 (Development of a standard library of background simulation codes)
Task 4 (R&D on radiopurity of materials and purification techniques) of
JRA1 (Low background techniques for deep underground science)
• Attendance to JRA1 meeting held in Edinburgh on 10th September 2004
 Participants:
• Heidelberg:
G. Heusser, B. Schwingenheuer
• Milano:
S. Capelli, O. Cremonesi, M. Pavan
• Zaragoza:
B. Beltrán, J. M. Carmona, S. Cebrián, H. Gómez, G.
Luzón, I. G. Irastorza, J. Morales, A. Rodríguez, J. Ruz, L.
Torres
• South Carolina (non-EU, on a self-financing basis)
S. Cebrián, Cosmogenic Induced Activity
IDEA meeting, Heidelberg, October 2004
 Detailed implementation plan for first 18 months
Outline of the talk
• Task 1: presentation of found results
• Task 2: description of codes and comparison
• Task 3: description and results of the activation study for TeO2
• Future work and summary
S. Cebrián, Cosmogenic Induced Activity
IDEA meeting, Heidelberg, October 2004
Task 1: Collection of available data on crosssections
Search for p/n activation cross-sections on targets of interest (Ge, Te)
on the literature and from nuclear data libraries
DELIVERABLE: Summary of non-existing measurements of
cross-sections of interest and existing reliable measurements which can
be used to test the codes
Available at IDEA website: http://idea.dipscfm.uninsubria.it/
Outline of this part
General description and found results for:
- EXFOR
- RNAL
- MENDL
- Library up to 1.7 GeV
- Individual refences
EXFOR (CSISRS in USA)
http://www.nndc.bnl.gov/nndc/exfor/, http://www-nds.iaea.or.at
• compilation of experimental nuclear reaction data
• easy searches into the SQL database, via web
• full access to data and references
• some s for (n,X) and (p,X) processes on Te and Ge targets
• p+Ge: some results for worrisome products like 60Co and 68Ge/68Ga
mainly from an irradiation experiment at 660 MeV
Yu.V.Aleksandrov et al,
Bulletin of the Russian Academy of Sciences - Physics, 59 (1995) 895.
• p+Te: some results for I, Sb, and Te products but not for
from an irradiation experiment at 1.7 GeV
60Co
mainly
E. Porras et al, NIM B 160 (2000) 73
• more data for Cu and Pb
information in EXFOR is not enough to make a complete activation study
but essential to check calculated results
S. Cebrián, Cosmogenic Induced Activity
IDEA meeting, Heidelberg, October 2004
RNAL (Reference Neutron Activation Library)
http://www-nds.iaea.or.at/ndspub/rnal/www/
• library of evaluated cross sections for neutron-induced reactions leading
to radioactive products
• format ENDF6
• restricted to 255 reactions: no result for Ge, s for some (n,g) processes on
Te isotopes and for different reactions on Se, Xe, Mo, Cd, Cu or Pb
not very useful for DBD activation studies, altough some results can be
considered for checking
MENDL-2 (Medium Energy Nuclear Data Library) and MENDL-2P
ftp://iaeand.iaea.or.at/
“Neutron reaction data library for nuclear activation and transmutation at intermediate
energies”, “Proton reaction data library for nuclear activation”, by Yu.N. Shubin et al.
• detailed excitation functions calculated using the ALICE family of codes, checked
against experimental data
• very wide range of targets and products, but no information on 60Co for Te isotopes
• independent results for n and p as projectiles
• only up to 100 MeV for neutrons and 200 MeV for protons
• used in GEANT4 for calculating isotope production
S. Cebrián, Cosmogenic Induced Activity
IDEA meeting, Heidelberg, October 2004
• comparison of MENDL-2P and EXFOR results for production of some I isotopes on nat Te
(equivalent cross-checks can be made for production of Zn, Ga, Ge and As isotopes on Ge)
MENDL is a valuable tool for activation studies, but with a very limited
energy range for cosmogenics
S. Cebrián, Cosmogenic Induced Activity
IDEA meeting, Heidelberg, October 2004
Production s libraries for n and p to 1.7 GeV
“Production and Validation of Isotope Production Cross-Section Libraries for Neutrons
and Protons to 1.7 GeV”, S. G. Mashnik et al, [arXiv:nucl-th/9812071].
“Study of Isotope Production in High Power Accelerators: Detailed Report”, K. A. Van
Riper et al, LA-UR-98-5379.
http://t2.lanl.gov/publications/publications.html
• evaluated library of excitation functions
including available experimental data and
calculated results using the most suitable
codes
products
• independent results for n and p as
projectiles
• up to 1.7 GeV
• covering ~1/3 of natural elements
• products of medical interest
This library can be very useful
specially for studying activation in
Ge DBD experiments
targets
S. Cebrián, Cosmogenic Induced Activity
IDEA meeting, Heidelberg, October 2004
S. Cebrián, Cosmogenic Induced Activity
IDEA meeting, Heidelberg, October 2004
Results from individual references on Ge
• Calculated neutron-induced excitation functions on natural Ge isotopes
for 68Ge, 65Zn, 58Co, A-2Ga and A-3Ga
F. T. Avignone et al., Nucl. Instr. B (Proc. Suppl.) 28A (1992)
and for 68Ge using LAHET
Majorana Collaboration, [arXiv.org:nucl-ex/0311013]
• Measured production of 60Co in Ge by p at 800 MeV
E. Norman, Poster at Neutrino 2004, Paris. To appear in NPB (PS).
EXFOR, 660 MeV
800 MeV
Results from individual references on Te and Mo
• Irradiation experiments at Berkeley with protons at 0.8, 1.85 and 5 GeV,
obtaining many production s, with recent evaluation of 60Co results
D. W. Bardayan et al, Phys. Rev. C 55 (1997) 820.
E. Norman, Poster at Neutrino 2004, Paris. To appear in NPB (PS).
S. Cebrián, Cosmogenic Induced Activity
IDEA meeting, Heidelberg, October 2004
Conclusions for Task 1
• Some experimental results are available for relevant production s
at fixed energies on Te and Ge from individual references and the
EXFOR database, coming from proton irradiation experiments
o Not sufficient for a complete activation study but extremely
useful to check complementary calculations
• The MENDL libraries offer reliable excitation functions for many
targets and products up to 100 MeV for n and 200 MeV for p
• Some evaluated excitation functions have been derived for some
products on Ge isotopes
S. Cebrián, Cosmogenic Induced Activity
IDEA meeting, Heidelberg, October 2004
Task 2: Analysis of computational codes for n/p
activation
Collect information on:
• Target materials and product isotopes covered
• Projectiles allowed
• Range of applicable energies
• Physical models included and/or experimental data sets
considered for cross-sections
• Checks with experimental data
• “Technical” information: language, code source, support, ...
DELIVERABLE: Report summarizing the features and
limitations of the existing codes, deciding on the most suitable ones to
be used/improved in the study of activation in DBD experiments
Coming soon …
Outline of this part
- Semiempirical codes
- Hadronic Monte Carlo codes
- General-purpose Monte Carlo codes
Semiempirical codes
Based on Silberberg&Tsao equations for cross-sections of different processes
producing residual nuclei (spallation, fission, …)
Ap. J. Suppl. 25 (1973) 315, Ap. J. Suppl. 25 (1973) 335, Ap. J. Suppl. 35 (1977) 129, Ap. J.
Suppl. 58 (1985) 873, Phys. Rep. 191 (1990) 351, Ap. J. 501 (1998) 911.
COSMO
modified versions with new releases of formulas
different outputs: production s, mass yield curves, activity
C. J. Martoff, P. D. Lewin, Comput. Phys. Commun. 72 (1992) 96.
S
for Ge and Cu
J. Bockholt, PhD thesis, University of Heidelberg, 1995.
YIELDX
provided by Tsao with the updated formulas
output: production s
S. Cebrián, Cosmogenic Induced Activity
IDEA meeting, Heidelberg, October 2004
Hadronic Monte Carlo codes
 Many families of codes based on the Monte Carlo simulation of the hadronic
interactions between nucleons and nuclei: HETC, CEM, LAHET, ISABEL, INUCL,
CASCADE, ALICE, SHIELD, MARS, GEM, LAQGSM, …
• Versions of many of them available at the Nuclear Energy Agency (NEA) Data
Bank:
http://www.nea.fr/html/dbprog/
• Someones compared and checked against experimental data in a global NEA
study (on O, Al, Fe, Co, Zr, and Au targets) :
“International Codes and Model Intercomparison for Intermediate Energy Activation Yields”,
NSC/DOC(97)-1, January 1997
http://www.nea.fr/html/science/pt/ieay
and extensively compared with particular measurements of production s
irradiating targets with protons
M. Gloris et al, NIMB 113 (1996) 429
R. Michel et al, NIMB 129 (1997) 153
Gilabert et al, NIMB 145 (1998) 293
Yu. E. Titarenko et al, [arXiv:nucl-ex/9908012]
S. G. Mashnik et al, [arXiv:nucl-th/0208075]
Yu. E. Titarenko et al, [arXiv:nucl-ex/0401034]
… and many more!
S. Cebrián, Cosmogenic Induced Activity
IDEA meeting, Heidelberg, October 2004
 Features of some codes (used to create a library, as considered the most reliable ones)
code
history
physics
LAHET • Developed at Los Alamos based on HETC (Oak
Ridge) adding ISABEL/VEGAS
• Version 2.8 available at NEA requiring MCNP
• Version 3 released in 2001 including INUCL and
ABLA
• Included in MCNPX 2.4
CEM
cascade
up to 3.5 GeV for
nucleons
+[preequilibtium]
+evaporation
+fission
• Started at Dubna
cascade
• CEM95 available at NEA and included in MCNPX +preequilibrium
2.4
+evaporation
• CEM2k included in MCNPX 2.5
• CEM2k merged with GEM2 (fission)
ALICE • ALICE91 available at NEA
• Many different versions: AREL, HMS-ALICE,
ALICE-IPPE…
• Used for the MENDL libraries
energy range
precompound
decay
10 MeV-5 GeV
up to ~200 MeV
the relative role of each process giving rise to nuclei production changes with targets, products and
projectile energies so for different activation problems the most suitable codes may be different
S. Cebrián, Cosmogenic Induced Activity
IDEA meeting, Heidelberg, October 2004
 Conclusions from intercomparison of codes
(even if not dealing with activation reactions of interest in DBD experiments)
• NEA study in 1997: calculations of activation yields may at best have
uncertainties of the order of a factor of two. Frequently, average deviations
are much larger (may go up to two or three orders of magnitude).
• Measurements during 90s: predictive power of many codes is good (~2) in
the near spallation region (products not far from the target) but worse in the
deep spallation region or and much worse in the fission region
• Recent efforts to improve description of fission and fragmentation:
o Merging some codes with fission models (CEM2k+GEM2,
LAQGSM+GEM2) agreements up to 20-40 % have been reported
S. Cebrián, Cosmogenic Induced Activity
IDEA meeting, Heidelberg, October 2004
General-purpose Monte Carlo codes
code
website
GEANT4
http://geant4.web.cern.ch
/geant4/
(C++)
FLUKA
http://www.fluka.org
(FORTRAN77)
MCNPX
http://mcnpx.lanl.gov/
(FORTRAN90)
How to save nuclei
production
Physical models and data
(G4IsoParticleChange) Different models available,
G4HadronicProcess:: based on parameterizations
GetIsotopeProduction (GEISHA), evaluated data
(MENDL) and theory
Info()
(including other codes: HETC,
INUCL, MARS)
RESNUCLEI
Neutron cross sections and/or
information on production of
estimator
residual nuclei available for Te
/ Ge in present version
FT8 RES tally
(version 2.5)
Includes LAHET 2.8 and
CEM95 (version 2.4) and
CEM2k, INCL4 and ABLA
(version 2.5)
the user can choose between different models and implementations to
describe the hadronic physics
S. Cebrián, Cosmogenic Induced Activity
IDEA meeting, Heidelberg, October 2004
Conclusions for Task 2
Semiempirical codes
+ wide coverage of targets and products
+ short calculation time and simplicity of use
- only proton-induced reactions
Monte Carlo codes
+ neutron activation studies possible
- very time-consuming (specially for some products)
General-purpose MC codes
+ wide coverage of projectiles, targets and energies in principle
+ easy availability and support
+ different models can be used for the hadronic physics
- not many comparisons with measurements of activation yields available
Which codes should we use in our DBD activation studies?
• Semiempirical routine YIELDX
• MC codes like GEANT4 / MCNPX trying different hadronic models
S. Cebrián, Cosmogenic Induced Activity
IDEA meeting, Heidelberg, October 2004
Task 3: Comparison of results for some
problems of interest
Study using different codes and comparing with data when possible
DELIVERABLE: Report comparing the performances of
different codes for particular problems of interest in DBD
• Identification of the most reliable codes
• Quantification of the uncertainties or spread in the estimates
• Identification of weak points of the codes when treating our problems
Preliminary results for open questions in activation for DBD
Problem of activation in TeO2
Relevant production s on Te and the
corresponding activation yields have
been estimated using YIELDX and
GEANT4 and have been compared with
all previous results
Outline of this part
- GEANT4 simulations
- comparisons with measured s
- comparisons of excitation functions
- activity yields
 GEANT4 simulations
• GEANT4 version 4.6.0.p01
• Projectiles: neutrons and protons
• Energy: discrete values from 10 MeV to 5 GeV
• Geometry: various samples of irradiation experiments implemented
o nat Te disk (diameter 3.1 cm, height 0.67 cm) from Berkeley measurements at
1.85 GeV
o CdTe box (5 x 5 x 2 mm3) from measurement at 1.7 GeV
• Hadronic physics: different models taken into consideration
o user-defined physics list: low and high energy parameterized models (LHEP) +
evaluated cross-section data for neutrons up to 20 MeV
o QGSP: theory driven model based on Quark Gluon String models
o LHEP-BIC: LHEP + Binary cascade code below 3 GeV
o LHEP-BERT: LHEP + Bertini cascade code below 3 GeV
o LHEP-PRECO: LHEP + preequilibrium decay model below 100 MeV
J. P. Wellisch, nucl-th/0306006, nucl-th/0306008, nucl-th/0306016
S. Cebrián, Cosmogenic Induced Activity
IDEA meeting, Heidelberg, October 2004
 Comparison datacalculations for s
1,E+02
Z=52, Te
• Results from p
irradiation on natural Te
at 1.85 GeV in Berkeley
vs GEANT4 simulation
with different models
sigma (mb)
1,E+01
1,E+00
1,E-01
117
119
A
measurement Berkeley
GEANT4 (QGSP_HP)
121
129
Silberberg & Tsao
GEANT4 (LHEP_BIC)
GEANT4
GEANT4 (LHEP_BERT)
1,E+01
Z=27, Co
Z=35, Br
Z=37, Rb
sigma (mb)
1,E+00
1,E-01
1,E-02
model
deviation factor F
user physics list
33.5
QGSP
17.4
LHEP-BIC
18.9
LHEP-BERT
2.3
model chosen
1,E-03
60
75
measurement Berkeley
GEANT4 (QGSP_HP)
76
A
77
Silberberg & Tsao
GEANT4 (LHEP_BIC)
S. Cebrián, Cosmogenic Induced Activity
82
84
GEANT4
GEANT4 (LHEP_BERT)
IDEA meeting, Heidelberg, October 2004
• Results for production
cross-sections on Te
from p irradiation at
1.85 GeV and at 1.7
GeV versus YIELDX
semiempirical estimates
and GEANT4
simulations
exp
YIELDX GEANT4
exp
YIELDX GEANT4
deviation
factor F
measurementmeasurement
3.3
GEANT4GEANT4
1.6
measurementGEANT4
1.9
measurementGEANT4
1.9
order of the best accuracy expected
in this kind of calculations
S. Cebrián, Cosmogenic Induced Activity
1.85 GeV
1.7 GeV
in mb
IDEA meeting, Heidelberg, October 2004
Production cross-section for 60Co
absorption of g+b emissions = continuum in 2b|0n region
1,E+02
significant
discrepancy
COSMO –
YIELDX in 1-3
GeV
1,E+01
sigma (mb)
1,E+00
1,E-01
1,E-02
1,E-03
1,E-04
1,E-05
10
100
1000
10000
100000
energy (MeV)
Silberberg &Tsao (YIELDX)
GEANT4
measurement Berkeley
modified COSMO
measurement CERN
YIELDX
S. Cebrián, Cosmogenic Induced Activity
IDEA meeting, Heidelberg, October 2004
Production cross-section for 124Sb
b emitter with Q=2904.5 keV
• Contribution to background levels of muon-induced neutrons
1,E+02
agreement
COSMO –
YIELDX
help to decide if muon-vetos can be necessary in CUORE
1,E+01
sigma (mb)
1,E+00
• Cosmogenically
induced activity in TeO2 crystals
acceptable
agreement
GEANT4 –
MENDL/
YIELDX
1,E-01
help to plan the construction and transport of crystals
1,E-02
1,E-03
1,E-04
124Sb in natTe
1,E-05
1
10
100
1000
10000
relevant
difference for
n/p activation
at low
energies
energy (MeV)
MENDL-2P
GEANT4 (p, LHEP_BERT)
GEANT4 (n,LHEP_PRECO)
YIELDX
GEANT4 (n, LHEP_BERT)
modified COSMO
MENDL-2
experiment 1.7 GeV
GEANT4 (p, LHEP_PRECO)
MENDL-2 below and YIELDX above 100 MeV
S. Cebrián, Cosmogenic Induced Activity
IDEA meeting, Heidelberg, October 2004
Production cross-section for 125Sb
b emitter with Q=766.7 keV (only in DM region)
1,E+03
1,E+02
sigma (mb)
1,E+01
1,E+00
1,E-01
1,E-02
1,E-03
1,E-04
1,E-05
125Sb in natTe
1,E-06
1
10
100
1000
10000
energy (MeV)
MENDL-2P
GEANT4 (p, LHEP_BERT)
GEANT4 (n, LHEP_PRECO)
YIELDX
measurement Berkeley
modified COSMO
MENDL-2
GEANT4 (n, LHEP_BERT)
GEANT4 (p, LHEP_PRECO)
MENDL-2 below and YIELDX above 100 MeV
S. Cebrián, Cosmogenic Induced Activity
IDEA meeting, Heidelberg, October 2004
 Cosmic neutron spectrum f(E):
• From modified COSMO:
D. Lal and B. Peters, Springer, 1967.
T. W. Armstrong et al, J. Geophys. Res. 78 (1973) 2715.
O.C. Allkofer and P.K.F. Grieder, Physics Data, 25-1, 1984.
• Parameterization based on measurements:
J. F. Ziegler, IBM Journal of Research and Development 42 (1998) 1.
1,E-03
n/cm2/s/MeV
1,E-04
E>20 MeV:
4.5 10-3 n/cm2/s
1.5 10-3 n/cm2/s
1,E-05
1,E-06
1,E-07
1,E-08
1,E-09
1,E-10
10
100
1000
10000
energy (MeV)
Ziegler parameterization
S. Cebrián, Cosmogenic Induced Activity
modified COSMO
IDEA meeting, Heidelberg, October 2004
 Results for activity in TeO2:
A  R (1  e
nuclide
 texp
)e tdec
T1/2
in mBq / kg
R   dE s ( E ) fn ( E )
for texp=4 months, tdec=2 years
modified
COSMO
(CUORE
Proposal)
s:
s:
MENDL/YIELDX
f: mod. COSMO
MENDL/YIELDX
f: Ziegler
60Co
5.27 y
0.2
0.024
0.022
124Sb
60.2 d
0.05
0.014 + 0.026
0.05 + 0.06
125Sb
2.76 y
15
6.2 + 6.3
22 +15
Contributions
below +
above 100
MeV
• Activity of 60Co is almost one order of magnitude smaller using YIELDX
cross-sections, regardless of the neutron spectrum used
• Sb activity could be higher (factor 2) considering other neutron spectrum
S. Cebrián, Cosmogenic Induced Activity
IDEA meeting, Heidelberg, October 2004
Conclusions for Task 3
From the activation study in TeO2
• GEANT4 has been used to estimate some production s in Te, compared
with available measurements
o At high energies, LHEP_BERT physics list gives the best agreement,
being the deviation factor ~2
o Deviations between YIELDX (Silberberg&Tsao) and GEANT4 are also
~2
• Excitation functions have been described combining MENDL and YIELDX
results below and above 100 MeV
• Activity yields for TeO2 crystals have been derived and compared with
previous estimates based on a modified COSMO
S. Cebrián, Cosmogenic Induced Activity
IDEA meeting, Heidelberg, October 2004
Future work
• Task 2: complete analysis of codes
• Task 3: continue the study of particular problems
• activation in TeO2
• activation in Ge
• Task 4: start the design of new irradiation experiments
S. Cebrián, Cosmogenic Induced Activity
IDEA meeting, Heidelberg, October 2004
Summary
• A report has been prepared describing the available sources of
data for isotope production cross sections of interest in DBD
experiments
• Semiempirical and Monte Carlo codes for activation studies are
being analyzed and compared to find the most suitable ones
• An study of the cosmogenic activation for TeO2 is underway
using different codes and available data
S. Cebrián, Cosmogenic Induced Activity
IDEA meeting, Heidelberg, October 2004