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TUNL Contributions in the US Nuclear Data Program
Nuclear Structure Data Evaluation Program J.H. Kelley (USNDP Structure Group Leader),
Jim Purcell, and Grace Sheu(H.R. Weller & Kent Leung)
We are responsible for nuclear structure evaluation in the A=2-20 mass region• Energy Levels of Light Nuclei reviews published in Nuclear Physics
A• ENSDF files for A=2-20• XUNDL from A=2-20
Web interface for A=3-20 Information
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Evaluation Activities• Energy Levels of Light Nuclei
– Follow style of Fay Ajzenberg-Selove– Broad scope of reactions is included – discussion
format. – Adopted levels/gammas, Energy Level Diagrams
• ENSDF– More rigorous information required– Better documentation of original sources– reaction data sets/decay data sets– Adopted levels/gammas, decay widths, etc.
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Adopted Levels g-ray transitions
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Present Evaluation ActivitiesPublished “Energy Levels of Light Nuclei: A=3”
Nucl. Phys. A848 (2010) 1“Energy Levels of Light Nuclei: A=11”
Nucl. Phys. A880 (2012) 88 (ENSDF Updated)
Work in progress:– A=12 Evaluation for “Energy Levels” (90%)– Preparing A=12 ENSDF file– Preparing A=3 ENSDF file(Jim Purcell)– Preparing A=2 ENSDF file(K. Leung & H.R. Weller)
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Evaluation Activities• Updated ENSDF nuclides
– 6B, 14F, 15Ne, 18Mg, 19Mg
• Updated ENSDF Reaction Data sets– b: 14Be, 14B, 19N, 20N– b-n: 12Be, 13B, 14Be, 14B, 15B, 16C, 17B, 17C, 17N, 18C, 18N,
19B, 19C, 19N, 20C, 20N– b-p: 9C, 11Be, 13O, – b-a: 9C, 11Be, 14Be, 17N, 18N, 20Na
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XUNDLCompilation Activities
• Experimental Unevaluated Nuclear Data Library– Up-to-date structure data Library– New articles added within 1-2 months– Feedback loop between source and evaluator– Committed to A=2-20 since April 2009– 60-65 data sets/year (5-6/month)– Organized “Workshop on the Future of XUNDL”
• TUNL May 16-17 2013
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Why XUNDL makes a difference
17Ne17Ne used for device
calibration
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Other Compilation Activities• Compilation of ground state decay & b-decay
references and data• Compilation of (p,X) and (a,X) excitation
functions• TUNL Dissertations-
– http://www.tunl.duke.edu/~gsheu/Theses/TUNL_Theses.shtml
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Synergistic Experimental ActivitiesHIGS FacilityCompton Backscattered Photons
Monoenergetic Neutron Sources at TUNLDD, DT, PT, and PLi
147Nd Absolute 239Pu Fission Product Yield
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HIGS FacilityCompton Backscattered Photons
TUNL and HIGS
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Nuclear Resonance Fluorescence Technique
TUNL and HIGS
Experimental Observables in NRF
HIGS Advantages
AXN
1-
Excitation energy Ex
Spin and parity J,
Decay width 0
Branching ratio i /
A.P. Tonchev, NIM B 241 51474 (2005)
G. Rusev, PRC 79, 047601 (2009)
In a completely model independent way !
σel = f(Eγ) (from primary g.s. transitions)
σinel = f(Eγ) (from secondary transitions)
σtot = σel + σinel = σabs
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High Intensity Gamma-ray SourceNuclear Resonance Fluorescence• Levels and Level Parameters• DHS/DNDO cargo container interrogation
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Spin and Parity Determination
TUNL and HIGS
N. Pietralla, at al. PRL 88 (2002) 012502; A. Tonchev, NIM B 241 (2005) 51474
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Spin and Parity Determination
TUNL and HIGS
N. Pietralla, at al. PRL 88 (2002) 012502; A. Tonchev, NIM B 241 (2005) 51474
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NRF from 238U
TUNL and HIGS
Over 105 new excited low-spin states in 238U were observed at γ-ray beam energies from 2.0 to 5.5 MeV.
80 E1 and 25 M1 states were identified
HIGS facility is an ideal source for identifying low-spin states
Samantha Hammond Ph.D. Project
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NRF from 235U
TUNL and HIGS
Eg = 1800 keV; ΔE/E = 70 keVm235U = 3.5 g; ti = 6 h; ϕγ = 3x107 γ/s
13 discrete deexcitations were identified for the first time in the from 1.6 to 3.0 MeV. This includes 10 to the ground state, two branching transitions to the third excited state
at 46.2 keV and one unresolved transition in 235U. Unique decay pattern
E. Kwan et al., accepted by PRC
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Monoenergetic Neutron Sources available at TUNLDD, DT, PT, and PLi, Sources
DENIS source FN TANDEM 10MV
Shielded neutron source area
Flux on target (107 - 108) cm-2 s-1
Energy spread dE/E = 0.1 to 0.402H(d,n)3He; Monoenergetic neutrons: 4.0 – 7.7 MeV
3H(p,n)3He; Monoenergetic neutrons: 0.5 – 7.7 MeV
Quasi-monoenergetic neutrons
7Li(p,n)7Be; Monoenergetic neutrons: 0.1 – 0.65 MeV
3H(d,n)4He; Monoenergetic neutrons: 14.8 – 20.5 MeV
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1. Motivation
2. Energy Dependence of Fission-Product Yields
3. Experimental technique
4. Results
5. Future plans
Modernizing the Fission Basis: Measurement of Fission Product Yields from Fast-Neutron-Induced Fission
for the LLNL-LANL-TUNL collaboration
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21
TUNLDukeC. BHATIAM. BHIKEB. FALLINC. HOWELLW. TORNOW N.C. State Univ.M. GOODENJ. KELLEY
LLNLJ. BECKERR. HENDERSONJ. KENNEALLYR. MACRIC. RYANS. SHEETSM. STOYERA. TONCHEV
LANLC. ARNOLDE. BONDT. BREDEWEGM. FOWLERW. MOODYR. RUNDBERGG. RUSEVD. VIEIRAJ. WILHEMY
Acknowledgements
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Motivation
Resolve the long-standing difference between LLNL and LANL with respect to selected fission product data
Joint LANL/LLNL fission product review panel endorsed a possible energy dependence of 239Pu(n,f)147Nd fission product yield with fission neutrons:
4.7%/MeV from 0.2 to 1.9 MeV (M. Chadwick)
3.2%/MeV from 0.2 to 1.9 MeV (I. Thompson)
Mostly low energy data from critical assembly or fast reactors
239Pu(n,f)147Nd
M.B. Chadwick et al. Nuclear Data Sheets 111 (2010) 2923; H.D Selby et al. Nuclear Data Sheets 111 (2010) 2891.P. Baisden et al, LLNL-TR-426165, 2010; R. Henderson et al. LLNL-TR-418425-DRAFT; I. Tompson et al. Nucl. Sci. Eng. 171, 85 (2012)
There are no 147Nd data between 1.9 and 14 MeV
Very scarce experimental data at the MeV-range
Large discrepancy (~20%) at 14 MeV
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Fission Fragment Distribution with Neutron Energy
YiE (A) = fractional yields of mass chain ‘A’ (after b decays) from initial
actinide ‘i’ for neutron energy ‘E’.
How does the asymmetry evolve with neutron energy for 235,238U, 239Pu?
Depends on actinide Depends on neutron energy
Goal: Develop high-precision FPY energy dependence from 1 to 15 MeV
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2H gas
From VdG accelerator
p or dn
One thick target ~0.2 g/cm2
Two thin targets ~10 μg/cm2
Dual fission chamber n-detector
Monoenergetic Neutron Irradiation
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Dual Fission Chamber: The Renaissance of the NIST idea
Design and fabricate three fission chambers: one for 239Pu, one for 235U, and one for 238U
Dedicated thin (~10 μg/cm2) 235,238U and 239Pu foils electroplated on 0.5” titanium backing★
Dedicated thick (200 - 400 mg/cm2) 235U (93.27%) 238U (99.97%) and 239Pu (98.4%) targets
Fission chamber efficiency confirmed: 100%, confirmed with activation measurements
★ Made by LANL
Gas flow in and out
FC
gas cell
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Fission Spectrum at En = 9.0 MeV
Excellent a / fission separation
alpha
fission
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FPY Ratios to 99Mo for 239Pu at 4.6, 9.0, 14.5, and 14.8 MeV
FP/ 99Mo
Present
Data
Present
Data
Present
Data
Present
Data
Gindler 1
et al.
LANL2
Selby et al.
Saclay3
J. Laurec et al.
England 4 et al.
LANL5 LLNL6
Nethaway
<Einc> 4.6 MeV 9 MeV 14.5 MeV 14.8 MeV 4.5 MeV 1.3 -1.5 MeV 14.7 MeV 14 MeV 14 MeV 14.8 MeV
87Kr91Sr92Sr97Zr
105Ru131I
132Te133I
140Ba142La143Ce147Nd
0.21 ± 5.3%0.52 ± 2.2%0.56 ± 4.3%0.96 ± 3.3%0.96 ± 3.7%
-0.83 ± 5.2%1.18 ± 5.0%0.89 ± 3.8%
-0.63 ± 3.9%0.37 ± 5.1%
0.22 ± 5.3%0.48 ± 1.4%0.51 ± 3.7%0.89 ± 2.9%0.85 ± 2.2%0.93 ± 3.3%0.76 ± 4.0%1.03 ± 3.5%0.82 ± 3.0%0.80 ± 2.1%0.64 ± 2.6%0.34 ± 3.9%
0.22 ± 5.5%0.52 ± 1.4%0.52 ± 3.7%0.97 ± 2.1%0.86 ± 2.0%1.03 ± 3.0%0.80 ± 4.0%1.09 ± 3.9%0.84 ± 2.3%0.85 ± 2.0%0.64 ± 2.3%0.35 ± 3.2%
0.21 ± 5.3%0.53 ± 1.8%0.52 ± 3.8%0.86 ± 2.7%0.86 ± 2.7%
-0.76 ± 4.9%0.88 ± 3.7%0.85 ± 2.8%0.90 ± 3.4%
-0.36 ± 4.6%
0.22 ± 4.5%0.51 ± 4.8%0.58 ± 6.4%0.93 ± 0.6%0.87 ± 6.0%
-0.84 ± 0.7%1.11 ± 0.6%0.88 ± 0.6%0.79 ± 5.9%0.65 ± 0.6%
-
0.77 ± 4.5%
----
0.85 ± 4.2%
-0.71 ± 5.2%
0.34 ± 3.5%
---
0.83 ± 3.3%-
0.61 ± 3.5%0.81 ± 4.5%0.99 ± 6.2%0.82 ± 3.1%
-0.67 ± 3.2%0.31 ± 5.2%
--
0.93 -
0.920.700.940.78
-0.590.36
0.86 ± 7.1 %0.74 ± 6.0 %0.97 ± 5.2 %0.61 ± 7.9 %0.74 ± 5.7 %0.74 ± 5.8 %
-0.34 ± 6.3 %
0.86 ± 7.1 %--
0.6 ± 7.1%-
0.72 ± 7.1 %
-0.33 ± 7.1 %
1 J.E.Gindler et al. Phys. Rev. C 27 (1983) 2058.2 H.D.Selby et al. Nucl. Data Sheets 111(2010)2891-2922.3 J. Laurec et al. Nucl. Data Sheets 111(2010)2965-2980.4 T.R. England and B.F. Rider, LA-UR-94-3106.5 M. Mac Innes, M.B. Chadwick, and T. Kawano, Nuclear Data Sheets 112 (2011) 3135–31526 D.R.Nethaway and B. Mendoza, Phys. Rev. C 6 (1972) 1827
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FPY Ratios to 99Mo for 235U and 238U at 4.6, 9.0, and 14.5 MeV
FP/ 99Mo PresentData
PresentData
Present
DataGlendenin et al. 1
ANLSelby et al. 2
LANLLaurec et al. 3
SaclayMaeck mass-spectrometry4
England et al.5
Innes et al. 6
LANLNethaway et
al.7
LLNL
<Einc> 4.6 MeV 9 MeV 14.5 MeV 3.9 MeV ~1.4 MeV 14.7 MeV 0.2-0.4 MeV 14 MeV 14 MeV 14.8 MeV238U
97Zr105Rh
131I132Te135Xe140Ba141Ce143Ce147Nd
0.86 ± 2.6 %0.55 ± 3.0 %
-0.74 ± 4.3 %
-0.79 ± 2.9 %
-0.70 ± 3.2 %0.35 ± 3.5 %
0.85 ± 2.4 %0.62 ± 3.3 %0.60 ± 2.7 %0.74 ± 4.5 %
-0.87 ± 2.8 %
-0.73 ± 3.1 %0.37 ± 2.8 %
0.97 ± 2.2 % 0.76 ± 3.4 %0.71 ± 2.2 %1.18 ± 5.4 %1.15 ± 3.4 % 0.93 ± 2.5 %0.88 ± 2.4 %0.87 ± 2.6 %0.40 ± 3.5 %
0.94 ± 0.2 %0.73 ± 0.4 %0.56 ± 0.2 %0.82 ± 0.3 %
-1.03 ± 0.5 %
-0.77 ± 0.4 %0.45 ± 0.4 %
----
0.92 ± 3.6 %--
0.42 ± 3.8 %
0.89 ± 3.4 %0.58 ± 5.0 %0.70 ± 3.4 %0.81 ± 4.7 %0.99 ± 4.8 %0.79 ± 3.3 %0.67 ± 3.5 %0.77 ± 3.2 %0.34 ± 5.4 %
-----
0.95 ± 2.4 %--
0.40 ± 1.8 %
0.930.570.690.811.020.880.530.700.37
0.89 ± 6.1 %0.57 ± 14.7 %0.71 ± 5.6 %0.82 ± 5.9 %
-0.80 ± 5.9 %
0.75 ± 5.9 % -
0.37 ± 5.6 %
0.88 ± 6.5 %----
0.78 ± 7.2 %-
0.86 ± 7.2 % 0.36 ± 7.0 %
235U 97Zr
105Rh131I
132Te140Ba143Ce147Nd
1.04 ± 4.4 %0.37 ± 2.5 %
-1.09 ± 4.6 %0.99 ± 3.6 %0.93 ± 3.8 %0.35 ± 4.3 %
1.04 ± 2.4 %0.39 ± 2.4 %0.91 ± 3.6 %1.08 ± 4.2 %1.05 ± 2.9 %0.93 ± 3.8 %0.30 ± 3.0 %
1.02 ± 1.8 %0.37 ± 1.8 %0.84 ± 2.4 %1.10 ± 3.3 %1.06 ± 2.5 %0.92 ± 2.6 %0.38 ± 2.7 %
1.09 ± 0.4 %-
0.73 ± 0.3 %0.94 ± 0.4 %1.07 ± 0.4 %0.86 ± 0.5 %0.41 ± 0.3 %
----
0.97 ± 3.3 %-
0.36 ± 3.4 %
0.98 ± 3.6 %-
0.86 ± 3.3 %0.81 ± 4.7 %0.89 ± 3.3 %0.72 ± 3.3 %0.30 ± 5.5 %
----
1.01 ± 1.4 %-
0.34 ± 1.4 %
1.010.360.800.790.880.740.32
0.99 ± 6.6 %0.37 ± 6.0 %0.89 ± 5.8 %0.81 ± 5.5 %0.89 ± 5.5 %
-0.32 ± 5.8 %
1 ± 13.9 %---
0.83 ± 10.6 %-
0.32 ± 11.9 %
1 L. E. Glendenin et al. Phys. Rev. C 24 (1981) 2600.2 H. D. Selby et al. Nucl. Data Sheets 111(2010)2891-2922.3 J. Laurec et al. Nucl. Data Sheets 111(2010)2965-2980.4 W.J. Maeck et al., ENICO – 1028 (1980).5 T.R. England and B.F. Rider, LA-UR-94-3106.6 M. Mac Innes, M.B. Chadwick, and T. Kawano, Nuclear Data Sheets 112 (2011) 3135–3152.7 D. R. Nethaway and B. Mendoza, Phys. Rev. C 6 (1972) 1827.
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239Pu FPY Ratios to 99Mo: at 4.6, 9.0, 14.5, and 14.8 MeV Preliminary
90 100 110 120 130 140 1500.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6 239Pu_TUNL
147Nd143Ce
140Ba
133I
132Te
131I97Zr
Mass Number of fission fragments
Yie
ld r
atio
( X
/ 9
9 Mo
) TUNL_4.6MeV TUNL_9MeV TUNL_14.5 MeV TUNL_14.8 MeV
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235U FPY Ratios with Respect to 99Mo: Comparison Preliminary
90 100 110 120 130 140 1500.0
0.5
1.0
1.5
2.0
147Nd
143Ce
140Ba132Te
131I
105Rh
97Zr
235U Y
ield
rat
io (
X /
99 M
o )
Mass Number of fission fragments
TUNL_9 MeV LA-UR-94-3106_14MeV Saclay_14.7 MeV LANL_1.3-1.5 MeV
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238U FPY Ratios with Respect to 99Mo: Comparison Preliminary
90 100 110 120 130 140 1500.0
0.5
1.0
1.5
147Nd
143Ce
140Ba132Te
131I
105Rh
97Zr
238UY
ield
rat
io (
X /
99 M
o )
Mass Number of fission fragments
TUNL_9 MeV LA-UR-94-3106_14MeV Saclay_14.7 MeV LANL_1.3-1.5 MeV
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239Pu FPY Ratios: 147Nd/99Mo at 4.6, 9.0, 14.5 and 14.8 MeV Preliminary
0 2 4 6 8 10 12 14 160.20
0.25
0.30
0.35
0.40
0.45
0.50
En (MeV)
FPY COMPARISON_239Pu14
7 Nd
/ 99M
o
TUNL Selby_LANL(2010) Laurec_Sachlay(2010) England(1994) Innes_LANL(2011) Nethway_LLNL(1972)
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147Nd Absolute Fission Product Yield Preliminary
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Comparison with Theory
1. Our absolute magnitude of the 147Nd FPY below 2.5 MeV and at 14.5 MeV neutron energies are slightly higher than the predicted values.
2. We can rule out the two low-yield data at 14.8 MeV.
3. The slope of 147Nd FPY from 4.6 to 14.8 MeV is slightly negative (-1% / MeV).
4. There is no energy dependence (or it is below our experimental sensitivity) for 140Ba and 99Mofragments.
Model calculation ___Uncertainties ___
J. Lestone. Nuclear Data Sheets 112 (2011) 3120
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SummaryWe start delivering precise (< 2% relative uncertainty) information on FPY ratios obtained at SIX energies in case of 239Pu and at FOUR energies for 235U and 238U
We will deliver accurate (4-5% absolute uncertainty) information on the energy dependent fission product yields covering an energy range from 1 < En < 15 MeV
Potential experiments:
Reduce 147Nd branching ratio uncertainty from the current 8%
High-accuracy measurements in the 0-2 MeV range to clarify 144Ce and 147Nd neutron-energy dependence
Strong LLNL-LANL-TUNL Collaborative Effort