ENDF/B-VIII: What has changed so far? · NUCLEAR DATA SHEETS M.B. Chadwick et al. agreement....
Transcript of ENDF/B-VIII: What has changed so far? · NUCLEAR DATA SHEETS M.B. Chadwick et al. agreement....
ENDF/B-VIII: What has changed so far?
D. Brown, National Nuclear Data Center, BNL
Critical assembly performance
Plot curtesy A. Trkov
So, what has changed and what hasn’t?
§ CIELO evaluations§ TSL evaluations§ Many other ENDF
evaluations§ V&V, QA§ New format
This is what gets us the amazing performance
So, what has changed and what hasn’t?
§ CIELO evaluations§ TSL evaluations§ Many other ENDF
evaluations§ V&V, QA§ New format
But many other applications need these
So, what has changed and what hasn’t?
§ CIELO evaluations§ TSL evaluations§ Many other ENDF
evaluations§ V&V, QA§ New format
This is how we insure good performance
So, what has changed and what hasn’t?
§ CIELO evaluations§ TSL evaluations§ Many other ENDF
evaluations§ V&V, QA§ New format
This is how we prepare for the future
Fraction of evaluations provided for ENDF/B-VIII
CSEWG is a long standing collaboration between data users who, incidentally, are also the biggest content providers
ENDF/B-VIII highlights§ CIELO:
• 16O• 56Fe• 235U• 238U• 239Pu
§ Neutron standards§ 1H§ 6Li§ 10B§ 197Au
§ Structural materials:§ 12,13C§ 40Ca• 54Fe, 57Fe, 58Fe• 58-61Ni• Yb, Dy, Os
(JENDL4)• 63,65Cu• 182,183,184,186W• 174,176,178,179,180Hf• 132Te
§ Other non-CIELO:• n• 7Be• 18O (RUSFOND)• 35,37Cl• 59Co• 73,74As• 78Kr• 124Xe• RQ Wright’s nubars• 40Ar• 236m1Np• 240Pu• EGAF gammas• Bug fixes
ENDF/B-VIII highlights§ CIELO:
• 16O• 56Fe• 235U• 238U• 239Pu
§ Neutron standards§ 1H§ 6Li§ 10B§ 197Au
§ Structural materials:§ 12,13C§ 40Ca• 54Fe, 57Fe, 58Fe• 58-61Ni• Yb, Dy, Os
(JENDL4)• 63,65Cu• 182,183,184,186W• 174,176,178,179,180Hf• 132Te
§ Other non-CIELO:• n• 7Be• 18O (RUSFOND)• 35,37Cl• 59Co• 73,74As• 78Kr• 124Xe• RQ Wright’s nubars• 40Ar• 236m1Np• 240Pu• EGAF gammas• Bug fixes
ENDF/B-VIII highlights§ CIELO:
• 16O• 56Fe• 235U• 238U• 239Pu
§ Neutron standards§ 1H§ 6Li§ 10B§ 197Au
§ Structural materials:§ 12,13C§ 40Ca• 54Fe, 57Fe, 58Fe• 58-61Ni• Yb, Dy, Os
(JENDL4)• 63,65Cu• 182,183,184,186W• 174,176,178,179,180Hf• 132Te
§ Other non-CIELO:• n• 7Be• 18O (RUSFOND)• 35,37Cl• 59Co• 73,74As• 78Kr• 124Xe• RQ Wright’s nubars• 40Ar• 236m1Np• 240Pu• EGAF gammas• Bug fixes
Bug fixes
§ Beta4 • 35,37Cl• 74As• 241Am
§ Beta5 (ENDF/A)• 48Ti• 10Be• 180,181Ta• 185,187Re
Serious changes
§ Beta4• 63,65Cu Covariances• 240Pu• Standards• CIELO
§ Beta5 ??• Standards• CIELO• 53Cr?
240Pu§ Resonances
• 2010 ORNL evaluation did not perform well, was rejected, but minor fix to bound level needed, V. Sobes made correction
§ Fast Region• Fission cross section updated: Replaced by Tovesson 2009 data from
5.7keV to 40 keV (URR), Weston 40keV - 190keV.• Capture cross section taken from ENDF/B-VII.0 (=ENDF-B/VI.8), with
an additional 2% reduction above 42 keV to improve• Elastic cross section taken from ENDF/B-VII.0 (=ENDF-B/VI.8).IAEA
noted problem in URR, ave. capture restored to VI.1
Capture in URR94-Pu-240(N,G),SIG
Incident Energy (keV)
Cro
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arns
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10 20 30 40 50 600.4
0.5
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1.0
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ENDF/B-VII.1:PU-240ENDF/B-VI:PU-240Pu240-beta4-Sobes
1977 Weston1972 Hockenbury1979 Wisshak1978 Wisshak
Final thermal constants; validation covered later in meeting
Neutron Reactions on XXX . . . NUCLEAR DATA SHEETS M.B. Chadwick et al.
agreement.(n,n’) inelastic scatteringAdd. Although we have not made many changes here,include plots of inelastic scattering compared to dataand other evaluations. Include key angular distributions,as in Ref.[92].
(n,2n)Only a modest change to the (n, 2n) cross section hasbeen made for ENDF/B-VIII.0 – the rise from thresholdhas been increased, in the 6.5 to 8 MeV incident energy,after which the cross section follows ENDF/B-VII.1.
The previous ENDF/B-VII.1 evaluation came from theGEANIE-project evaluation by LLNL and LANL [100].In the late 1990s and early 2000s, the GEANIE detectorat Los Alamos measured gamma-ray decays contribut-ing to the (n, 2n) reactions, and these data were aug-mented by GNASH model calculations for unmeasuredcomponents to infer the (n, 2n) cross section. The finalevaluation, used in ENDF/B-VII, was based on a least-squares (covariance) analysis of these data together withthe 1980s 14 MeV Lougheed [101] radiochemical data, asshown in Fig. ??. Other data such as those from Frehaut,and from Mather, were not used in the analysis becausetheir uncertainties were felt to be too high.
Some integral feedback on the production of 238Pu ina fission spectrum has suggested that this cross sectionshould rise from its threshold somewhat faster. For ex-ample the PROFIL experiment suggested the need fora 25% higher cross section [81], in the threshold region,though internal LANL studies indicate the need for amuch smaller increase. Therefore the evaluation has beenmodified in ENDF/B-VIII.0 to follow the upper errorbars on the 7 – 7.5 MeV GEANIE data, as shown inFig. ??.(n,xn) secondary neutron spectraAdd. Include 14 MeV and other (n,xn) plots.
Gamma production and (n,f) PFGSAdd TK’s work with Ionel’s fission PFGS.
Future workIn the coming years we expect to see new plutoniumprompt fission spectra (PFNS) and fission cross sectiondata from the Los Alamos Chi-nu and TPC experiments,and these will influence future standards and ENDF eval-uations. These data, together with the DANCE detectorneutron capture measurements, will be used in evalua-tion updates in the resonance region as well as the fastregion. The thermal plutonium PFNS clearly needs moreattention. The spectrum we have adopted is very similarto that in ENDF/B-VII, and – together with Subgroup34 resonances – allows an improved prediction of thermalsolution plutonium criticality relative to previous evalu-ations. However, it is not consistent with the somewhatsofter thermal spectra adopted for 235U and the recom-mendations of Ref. [10], nor with the trends seen in thesomewhat softer PFNS adopted for ENDF/B-VIII.0 for
fast energies in the 0.5-5 MeV region, as seen in Fig.??Neutron inelastic scattering has not been changed in
this latest revision of ENDF. More work will be done toassess the accuracy of the current evaluation; in partic-ular, the semi-integral scattering technique pioneered byRPI, which have provided useful data for 238U, C, Fe, willbe applied to plutonium and uranium, at the LANSCEfacility. Such future data should provide a useful valaida-tion check on the database, and point to improvementsthat may be needed in the magnitude and the angulardistributions of inelastic and elastic scattering processes.
6. 240Pu
Lead: BNL, ORNL, LANL Lead: BNL, ORNL,LANLBackground & Previous Evaluationstmp
Resonance RegionThe negative (bound) levels of the Derrien, et al. [121]RRR evaluation were adjusted with the evaluation codeSAMMY to better match the thermal cross section val-ues found in the Atlas of Neutron Resonances (Table IV).The resonance parameter covariance matrix was adjustedaccordingly to preserve the relative uncertainty of thecross section in the original evaluation of Derrien etal. [121]
TABLE IV. Thermal quantities for 240Pu at293.6 K = 0.0253 eV
Quantity Atlas ENDF/B-VIII.0 ENDF/B-VII.1�� 289.5 ± 1.4 b 289.4 b 287.5 b�s 1.73 ± 0.10 b 1.73 b 0.95 b�f 0.056 ± 0.030 b 0.056 b 0.064 b�B 18.8 b 17.96 b 3.02Wescott’sg-factor 1.0264 1.0259 1.0278
7. 241Am
Lead: LANL
8. 243Am
Lead: LANL
E. Primary gammas
Lead: LLNL
42
ENDF/B-VIII highlights, continued§ Charged
particles:• p+d, p+7Li, p+a,
p+13C, p+207Pb• d+7Li• t+a, t+7Li• 3He+a, 3He+3He• a+a
§ EPICS2014:§ photoat§ electrons§ atomic_relax
§ Decay data:• 93,95,96Rb• 95Sr• 82,83Ge• 95,98,98m,99Y• 88,89,90,91Br• 90Kr• 140,141Cs• 143Ba• 143,144,145La• 134Sb• 138I
§ Thermal Scattering:• Be(metal)• UO2 (x2)• Regular & reactor
graphite• BeO (x2)• Polyethylene• SiO2 (x2)• SiC• Lucite• UN• Water: H2O & D2O
(x2)• Water Ice Ih (x2)• YH2 (x2)
ENDF/B-VIII highlights, continued§ Charged
particles:• p+d, p+7Li, p+a,
p+13C, p+207Pb• d+7Li• t+a, t+7Li• 3He+a, 3He+3He• a+a
§ EPICS2014:§ photoat§ electrons§ atomic_relax
§ Decay data:• 93,95,96Rb• 95Sr• 82,83Ge• 95,98,98m,99Y• 88,89,90,91Br• 90Kr• 140,141Cs• 143Ba• 143,144,145La• 134Sb• 138I
§ Thermal Scattering:• Be(metal)• UO2 (x2)• Regular & reactor
graphite• BeO (x2)• Polyethylene• SiO2 (x2)• SiC• Lucite• UN• Water: H2O & D2O
(x2)• Water Ice Ih (x2)• YH2 (x2)
ENDF/B-VIII highlights, continued§ Charged
particles:• p+d, p+7Li, p+a,
p+13C, p+207Pb• d+7Li• t+a, t+7Li• 3He+a, 3He+3He• a+a
§ EPICS2014:§ photoat§ electrons§ atomic_relax
§ Decay data:• 93,95,96Rb• 95Sr• 82,83Ge• 95,98,98m,99Y• 88,89,90,91Br• 90Kr• 140,141Cs• 143Ba• 143,144,145La• 134Sb• 138I
§ Thermal Scattering:• Be(metal)• UO2 (x2)• Regular & reactor
graphite• BeO (x2)• Polyethylene• SiO2 (x2)• SiC• Lucite• UN• Water: H2O & D2O
(x2)• Water Ice Ih (x2)• YH2 (x2)
Also, added LEAPR inputs for all TSL evaluations except the General Atomics benzene evaluation from 1969
Bug fixes
§ Beta4• Be(metal)
§ Beta5 (ENDF/A)• p+2H• D2O (D, O)• H2O (H)
Serious changes
§ Beta4• Light charged particles• UN
§ Beta5 ??• nothing planned
UN: New TSL evaluation from NCSU§ LEAPR from NJOY99.396§ 7 temps. (296K-120K)§ Inelastic uses Incoherent approx. § Elastic uses generalized coherent
approx. with modified LEAPR
10-2 10-1 10010-3
10-2
10-1
100
10-2 10-1 100 10110-3
10-2
10-1
100
= 0.5409
= 5
.134
= 3
.941
= 3
.025
= 1.8
93 = 1.00
5
SS(,)
= 0
(a) U(UN)
= 0.5409
= 5
.134 = 3.
941
= 3
.025
= 1.893
= 1.0
05
SS(,)
= 0
(b) N(UN)
10-5 10-4 10-3 10-2 10-1 10010-1
100
101
102 ENDF/B-VIII: total ENDF/B-VIII: inelastic ENDF/B-VIII: coherent elastic ENDF/B-VIII: incoherent elastic
1200 K800 K600 K400 K
Cro
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Energy (eV)
296 K
Light charged particle evaluationsp td h 6Lia 7Li
p
d
t
h
a
RecommendECPLinfuture
KeepENDF/B-VII.0
Target: Projectile:
HereECPLtoENDF/B-VIII.0
p+7Li
0 4 8 12Incident proton energy (MeV)
0
0.02
0.04
0.06
0.08
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ectio
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Abramovitch, 19840.5x Spinka, 19710.5x Mani, 1964Sarma, 19630.5x Cassagnou, 1963Lee, 1969Rolfs, 1986Gibbons, 19990.5x Sawyer, 1957Gibbons, 19990.5x Ciric, 1976ENDF/B-VII.0ENDF/B-VIII.0
7Li(p,a)4He
0 5 10 15Incident proton energy (MeV)
0
0.1
0.2
0.3
0.4
0.5
0.6
Cro
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Abramovitch, 1964Abramovitch, 1964Presser, 1972Burke, 1974Newsom, 1957Poppe, 1976Bevington, 1961Borchers, 1963Schery, 1977Sekharan, 1976Sekharan, 1976Burke, 1974Liskien, 1975Liskien, 1975Sekharan, 1976Gibbons, 1959ENDF/B-VII.0ENDF/B-VIII.0 : gsENDF/B-VIII.0 : exENDF/B-VIII.0 total
7Li(p,n)7Be
P. Navratil merged ECPL cross sections with fits in literature; D. Brown added outgoing distributions from ECPL using inverse kinematics when needed
d+7Li
5 10 15 20Incident Deuteron Energy (MeV)
0
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0.1
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Vysotskij, 1990Guzhovskij, 1980ENDF/B-VIII.0
7Li(d,2n)7Be
1 10Incident Deuteron Energy (MeV)
0
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0.25
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Weissman 1998Filipone, 1982Kavanagh, 1960Schilling, 1976Filippone, 1982Elwyn, 1982Schilling, 1976Mingay, 1979Parker, 1966ENDF/B-VIII.0
7Li(d,p)8Li
1 10Incident Deuteron Energy (MeV)
0
0.05
0.1
0.15
0.2
Cro
ss s
ectio
n (b
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Macklin, 1955ENDF/B-VII.1ENDF/B-VIII.0
7Li(d,t)6Li
0 5 10 15 20Incident Deuteron Energy (MeV)
0
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0.4
0.6
0.8
Cro
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Ma Weiyi, 1980ENDF/B-VII.1ENDF/B-VIII.0
7Li(d,n+α)4He
t+7Li & 3He+3He
0.01 0.1 1 10Incident 3He Energy (MeV)
0
2
4
6
8
10
S-fa
ctor
(MeV
.b)
WA66BA67DW71DW74KR87BR87AR97BO99ENDF/B-VII.1ENDF/B-VIII.0
3He(3He,2p)4He
0 5 10 15 20 25 30
Incident Triton Energy (MeV)
0
0.5
1
Cro
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ecti
on
(b
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ENDF/B−VIII.0
7Li(t,2nα)α
10−1
100
101
Incident Triton energy (MeV)
0
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0.06
Cro
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(b
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Brune, 1991ENDF/B−VIII.0
7Li(t,n)
9Begs
Elastic scattering on 4He
0 2 4 6 8 10 12 14 16 18 20
Incident projectile energy (MeV)
0
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3E
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ctiv
e c
ross
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b)
0 2 4 6 8 10 12 14 16 18 200
2
p−4He MT=2 MF=3
t−4He MT=2 MF=3
h−4He MT=2 MF=3
α−4He MT=2 MF=3
More to come
§ 235,238U§ 239Pu § 54,56,57,58Fe§ Covariances§ C
ENDF/B-VIII planned for late FY17
6 year timeline not to scale
CSEWG Nov. 2016
WPEC May. 2016
ND2016 Sep. 2016
Mini CSEWG Apr. 2016
rev. 8108 Apr. 2016
rev. 82525 Apr. 2016
rev. 91919 Aug. 2016
rev. 10182 Nov. 2016
rev. 58622 Dec. 2011
rev. 108928 Feb. 2017
beta5: covariancelate spring 2017
beta6: release candidatesummer 2017
ENDF/B-VIII.0 latesummer 2017
Mini-CSEWG 4-5 May 2017
WPEC 15-19 May 2017
ENDF Hackathon©
2016
rev. 105119 Jan. 2017 ENDF/B-VII.0 contains 393
neutron evaluations; 1644 citations since 2006 (Google Scholar)ENDF/B-VII.1 contains 423 neutron evaluations; 945 citations since 2011 (Google Scholar)