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92-U -235 ORNL,LANL,+EVAL-NOV89 WESTON, YOUNG, POENITZ, LUBITZ
DIST-JAN09 20090105
----JEFF-311 MATERIAL 9228
-----INCIDENT NEUTRON DATA
------ENDF-6 FORMAT
*************************** JEFF-3.1.1 *************************
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** Original data taken from: JEFF-3.1 **
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***************************** JEFF-3.1 *************************
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** Original data taken from: JEFF-3.0 **
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05-01 NEA/OECD (Rugama) 8 delayed neutron groups
Jefdoc-976(Spriggs,Campbel and Piksaikin,Prg Nucl Eng 41,223(2002)
***************************** JEFF-3.0 ************************
DATA TAKEN FROM :- ENDF/B6-rel 5 (DIST-NOV98)
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A. Nouri, NEA/Data Bank
Format correction in line 4 of MF 1 MT 455
following a processing problem with NJOY97.107.
Change of TAB1 paramaters L1 and L2 from 1 1 to 0 0
Change of Q_val for MF/MT = 3/54 to -5.1701E+4 eV
ENDF/B-VI MOD 6 Revision, October 1997, L.C. Leal, H. Derrien,
N.M. Larson, and R.Q. Wright (ORNL)
1. New resonance parameter analysis; File 2, MT=151.
2. Total and prompt-nubar revised below 2 eV; File 1, MT=451,
452,456.
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File 2
MT=151 Resonance parameters, from a new analysis by Leal
et al. [LE97], using the multilevel R-matrix analysis code
SAMMY [LA96]. Energy range for U235 is 0 to 2.25 keV.
For the first time, integral data were fitted during the
analysis process: Thermal cross sections (fission,
capture, and elastic), Westcott g-factors (fission and
absorption) are from the ENDF/B-6 standards [CA93], and
the K1 value is from Hardy [HA79].
Thermal parameters obtained in the present evaluation,
first using the microscopic experimental data only, and
second including the integral data as well, are compared
to the SAMMY input in the following Table:
Parameter SAMMY input Fit to Fit to diff.
value diff data & integ.
alone data
----------- ----------------- -------- ------------
Fission 584.25 +/- 1.11 582.28 584.88
Capture 98.96 +/- 0.74 99.18 98.66
Scattering 15.46 +/- 1.06 15.44 15.12
Westcott gf 0.9771 +/- 0.0008 0.9743 0.9764
Westcott ga 0.9790 +/- 0.0008 0.9774 0.9785
Westcott gg 0.9956 0.9910
K1(barn) 722.70 +/- 3.90 717.48 722.43
The final adjustment of nu by SAMMY to the recommended K1
value of 722.7 gave nu = 2.4367 +/- 0.0005, with fission
and absorption cross sections calculated from the final
resonance parameters.
In the following Tables, the fission and capture cross
sections calculated in this evaluation with the code
SAMMY are compared with experimental data.
Experimental and calculated total cross sections.
Energy Range Calculated Schrack Weston Weston
(eV) (b.eV) (b.eV) (b.eV) (b.eV)
--------------- ---------- ------- ------ ------
0.5 - 20.0 910.4 929.9
20.0 - 60.0 1867.8 1882.8 1869.9
60.0 - 100.0 954.0 968.0 954.2
100.0 - 200.0 2032.7 2092.7 2089.5 2073.9
200.0 - 300.0 2062.2 2007.0 2060.0 2054.6
300.0 - 400.0 1280.8 1321.6 1297.1 1292.9
400.0 - 500.0 1333.2 1391.5 1351.8 1347.9
500.0 - 600.0 1489.2 1467.9 1499.2 1494.3
600.0 - 700.0 1126.6 1156.4 1134.1 1132.6
700.0 - 800.0 1088.7 1085.8 1093.3 1075.7
800.0 - 900.0 797.6 784.0 813.0 804.9
900.0 - 1000.0 724.4 723.9 738.2 721.4
1000.0 - 2000.0 7036.1 7054.2
Experimental and calculated capture cross sections.
Energy Range Calculated De Saussure Perez
(eV) (b.eV) (b.eV) (b.eV)
--------------- ---------- ----------- ------
0.5 - 20.0 653.5 647
20.0 - 60.0 1066.1 1084 1057
60.0 - 100.0 490.2 477 504
100.0 - 200.0 1158.8 1148 1138
200.0 - 300.0 907.8 904 940
300.0 - 400.0 660.2 658 642
400.0 - 500.0 495.9 506 478
500.0 - 600.0 533.3 506 562
600.0 - 700.0 494.8 481 449
700.0 - 800.0 490.1 513 475
800.0 - 900.0 439.8 444 397
900.0 - 1000.0 504.2 542 482
1000.0 - 1100.0 509.6 522 463
1100.0 - 1200.0 413.7 395 332
1200.0 - 1300.0 340.4 372 267
1300.0 - 1400.0 304.1 304 225
1400.0 - 1500.0 355.7 301 254
--------------- ---------- ----------- ------
20.0 - 1500.0 9164.7 9046 8665
The fission and capture resonance integral calculated from
the present evaluation are 276.04 b and 140.49 b, respectively,
giving a capture-to-fission ratio (alpha value) of 0.509 in
excellent agreement with the value obtained from integral
measurements.
The following energy-differential data were included in the
analysis:
(1) Transmission data of Harvey et al. [HA86] on the ORELA
18-meter flight path, with sample thickness of 0.03269
atoms/barn, cooled to 77 K (0.4 to 68 eV).
(2) Transmission data of Harvey et al. [HA86] on the ORELA
80-meter flight path, with sample thickness of 0.00233
atoms/barn, cooled to 77 K (4 to 2250 eV).
(3) Transmission data of Harvey et al. [HA86] on the ORELA
80-meter flight path, with sample thickness of 0.03269
atoms/barn, cooled to 77 K (4 to 2250 eV).
(4) Fission data of Schrack [SC88] on the RPI Linac at 8.4
meter flight path (0.02 to 20 eV).
(5,6) Fission and capture data of de Saussure et al. [DE67]
on the ORELA 25.2-meter flight path (0.01 to 2250 eV).
(7,8) Fission and capture data of Perez et al. [PE73] on the
ORELA 39-meter flight path (0.01 to 100 eV).
(9) Fission data of Gwin et al. [GW84] on the ORELA 25.6-meter
flight path (0.01 to 20 eV).
(10) Transmission data of Spencer et al. [SP84] on the ORELA
ORELA 18-meter flight path, sample thickness of 0.001468
atom/barn (0.01 to 1.0 eV).
(11) Fission data of Wagemans et al. [WA88] on the Geel 18-
meter flight path (0.001 to 1.0 eV)
(12,13) Absorption and fission data of Gwin [GW96] at ORELA
(0.01 to 4.0 eV).
(14) Fission data of Weston and Todd [WE84] on the ORELA
18.9-meter flight path (14 to 2250 eV).
(15) Eta data of Wartena et al. [WA87] at 8 meters (0.0018 to
1.0 eV).
(16) Eta (chopper) data of Weigmann et al [WE90] (0.0015 to
0.15 eV).
(17) Fission data of Weston and Todd [WE92] on the ORELA
86.5-meter flight path (100 to 2000 eV).
(18) Fission yield data of Moxon et al. [MO92] at ORELA
(0.01 to 50.0 eV).
----------------------------------------------------------------
REFERENCES FOR RESOLVED RESONANCE REGION
[CA93] A. Carlson, W.P. Poenitz, G.M. Hale et al., "The ENDF/B-6
Neutron Cross Section Measurements Standards," National
Institute of Standards and Technology report NISTIR-5177
(1993)
[DE67] G. de Saussure, R. Gwin, L.W. Weston, and R.W. Ingle,
"Simultaneous Measurements of the Neutron Fission and Capture
Cross Section for 235U for Incident Neutron Energy from
0.04 eV to 3 keV," Oak Ridge National Laboratory report
ORNL/TM-1804 (1967)
[GW84] R. Gwin, R.R. Spencer, R.W. Ingle, J.H. Todd, and S.W.
Scoles, Nuc.Sci.Eng. 88, 37 (1984)
[GW96] R. Gwin, To be published in Nuclear Science Engineering
[HA79] J. Hardy, Brookhaven National Laboratory, report
BNL-NCS-51123 [ENDF-300] (1979) Sec. B.1
[HA86] J.A. Harvey, N.W. Hill, F.G. Perey et al., Nuclear Data
for Science and Technology, Proc. Int. Conf. May 30-June 3,
1988, Mito, Japan. (Saikon Publishing, 1988) p. 115
[LA96] N.M. Larson, "Updated Users' Guide to SAMMY" report
ORNL/TM-9179/R3 (1996)
[LE97] L.C. Leal, H. Derrien, N.M. Larson, R.Q. Wright,
"R-Matrix Analysis of 235U Neutron Transmission and Cross
Sections in the Energy Range 0 eV to 2.25 keV," Oak Ridge
National Laboratory report ORNL/TM-13516 (1997).
[MO92] M.C. Moxon, J.A. Harvey, and N.W. Hill, private
communication, Oak Ridge National Laboratory (1992).
[PE73] R.B. Perez, G. de Saussure, and E.G. Silver, Nucl.Sci.
Eng. 52, 46 (1973)
[SC88] R.A. Schrack, "Measurement of the 235U(n,f) Reaction from
Thermal to 1 keV," Nuclear Data for Science and Technology,
Proc. Int. Conf. May 30-June 3, Mito, Japan (Saikon
Publishing, 1988) p. 101
[SP84] R.R. Spencer, J.A. Harvey, N.W. Hill, and L. Weston,
Nucl.Sci.Eng. 96, 318 (1987)
[WA87] J.A. Wartena, H. Weigmann, and C. Burkholz, report IAEA
Tecdoc 491 (1987) p.123
[WA88] C. Wagemans, P. Schillebeeckx, A.J. Deruyter, and R.
Barthelemy, "Subthermal Fission Cross Section Measurements
for 233U and 239Pu," Nuclear Data for Science and Technology,
Proc. Int. Conf. May 30-June 3, Mito, Japan (Saikon
Publishing, 1988) p. 91
[WE84] L.W. Weston and J.H. Todd, Nucl.Sci.Eng. 88, 567 (1984)
[WE90] H. Weigmann, P. Geltenbort, B. Keck, K. Shrenckenbach,
and J.A. Wartena, The Physics of Reactors, Proc. Int. Conf.,
Marseille, 1990, Vol.1 (1990) p. 133
[WE92] L.W. Weston and J.H. Todd, Nucl.Sci.Eng. 111, 415 (1992)
****************************************************************
ENDF/B-VI MOD 5 Revision 4 (R.Q.Wright, ORNL, V. McLane, NNDC,
October, 1996)
File 1, MT=451: Update of comments.
File 1, MT=456: Update of prompt nubar.
*****************************************************************
ENDF/B-VI MOD 4 Revision, February 1995, C. Lubitz (KAPL)
The resonance parameters below 900 eV were adjusted as described
in C.R. Lubitz, "A modification to ENDF6 U235 to increase
epithermal alpha and K1", Proceedings of the Int. Conf. on
Nuclear Data for Science and Technology, Gatlinburg, TN, May
9-13, Vol. 2 (American Nuclear Soc., 1994) page 646.
*****************************************************************
ENDF/B-VI MOD 3 Revision 2
Missing File 1 section 458 added.
*****************************************************************
ENDF/B-VI MOD 2 Revision, L. Weston (ORNL)
FILE 1: The uncertainties on the fission cross section
recommended by the Standards Committee of CSEWG are listed. The
updated description of File 2, the resolved resonance parameters,
is given.
FILE 2: The resolved resonance parameters have been changed
extensively. The neutron energy region below 4 eV has been made
a separate group. Eta decreases with decreasing neutron energy
below 0.1 eV. At the higher neutron energies, the resonance
parameters are more refined.
FILE 3: Smooth cross sections above 100 keV have minor
corrections.
FILE 31: Nubar covariance files were updated.
FILE 33: All covariance files were removed as correct new files
are not yet available.
*****************************************************************
ENDF/B-VI, MOD 1 Evaluation, April 1989
Principal evaluators:
Thermal parameters: Standards Committee of CSEWG.
Resolved resonance region: (0-2250 eV) L.C. Leal (U.Tenn.),
G. deSaussure (ORNL), R.B. Perez (U.Tenn.), N.M. Larson
(ORNL), M.S.Moore (LANL), and R.Q. Wright (ORNL).
Replaced by revision 6.
Unresolved resonance region and File 3 below 100 keV and the
capture cross section above 100 keV: W.P. Poenitz (ANL) and
L.W. Weston (ORNL)
Fission cross section above 100 keV: W.P. Poenitz (ANL) and the
Standards Committee of CSEWG.
Model calculations and fits above 100 keV: P.G. Young (LANL),
R.E. MacFarlane (LANL), and E.D. Arthur (LANL).
Covariance files: R.W. Peelle (ORNL). All files reoved in
revision 1, except MT=456.
File 1 Descriptive and Nubar Information -----------------------
MT=452 Total nubar. Replaced in revision 6.
MT=455 Delayed neutron yields from England [EN89].
MT=456 Prompt neutron yields. Replaced in revision 6.
FISSION CROSS SECTION UNCERTAINTIES: The CSEWG Standards
Committee supplied the following uncertainties with the these
statements. "These uncertainties are estimates such that if a
modern day experiment were performed today on a given standard
using the best techniques, those results should fall within these
expanded uncertainties (2/3 of the time). They take into account
inconsistencies and concerns about R-matrix parameters. Note
that it is not assumed that the uncertainties are totally
correlated within the energy ranges given."
Energy (keV) Estimated Comb Result (%)
Uncertainty (%)
2.53E-05 0.2 (0.19)
150-600 1.5
600-1000 1.6 (0.60)
1000-3000 1.8
3000-6000 2.3 (0.69)
6000-10000 2.2
10000-12000 1.8 (1.14)
12000-14000 1.2
14000-14500 0.8 (0.55)
14500-15000 1.5
15000-16000 2.0 (0.97)
16000-17000 2.5
17000-19000 3.0 (1.26)
19000-20000 4.0
File 2. RESOLVED AND UNRESOLVED RESONANCE PARAMETERS ----------
MT=151
Resolved resonance region: replaced in revision 6.
Unresolved resonance region:
The unresolved resonance region was derived by a FITACS
(Fritz Froehner code) fit by L.W. Weston to the Standards
Committee recommendation for the fission cross section and
new capture evaluation based on newer alpha measurements
(see ANL-83-4 supplement). These results were then fit
with URES (Ed Pennington code) so ENDF would reproduce.
unresolved resonance region extends from 2.25 to 25 keV
and is used only for self shielding calculations. Dilute
cross sections are taken from File 3 which shows
experimentally observed structure carried over from
version 5 up to 100 keV.
File 3. SMOOTH CROSS SECTIONS ----------------------------------
Model calculations from LANL: P.G. Young, R.E.MacFarlane,
E.D.Arthur. The evaluation above 100 keV is based on a detailed
theoretical analysis utilizing the available experimental data.
Coupled channel optical model calculations with the ECIS code
[Ra70] were used to provide the total, elastic, and inelastic
cross sections to the first 3 members of the ground state
rotational band, as well as neutron elastic and inelastic
angular distributions to the rotational levels. The ECIS code
was also used to calculate neutron transmission coefficients.
Hauser-Feshbach statistical theory calculations were carried out
with the GNASH [Ar88,Yo77] and COMNUC [Du70] code systems,
including preequilibrium and fission. DWBA calculations were
performed with the DWUCK code [Ku70] for several vibrational
levels, using B(El) values inferred from (d,d') data on U234,
U235, U238, as well as Coulomb excitation measurements. A weak
coupling model [Pe69] was used to apply the U234 and U238
results to states in U235.
A preliminary description of the analysis was given at the
Mito conference [Yo88].
MT=1 SUM OF PARTIAL CROSS SECTIONS FROM 2.25 TO 100 KEV.
0.10 to 20 Mev, obtained from a covariance analysis of
available experimental data, using an initial or prior cross
section from the coupled-channel optical model analysis.
Experimental data used include [Fo71], [Ve80], [Bo72], [Po81],
[Gr73], [Sc74], [Po83], [Pe60], [Wh65], [Ca73], and [Br58].
The GLUCS code was used for analysis [He80].
MT=2 UNCHANGED FROM VERSION 5 FROM 2.25 TO 100 KEV.
0.12 to 20 MeV, based on subtraction of (MT=4,16,17,18,37,102)
from MT=1.
MT=4 Sum of MT=51-91
MT=16 GNASH Hauser-Feshbach statistical/preequilibrium calc.
MT=17 GNASH Hauser-Feshbach statistical/preequilibrium calc.
MT=18 2.2 to 120 keV: average values from simultaneous
evaluation of W.P. Poenitz with structure carried over from
version 5. Renormalizaion was over 3 ranges per decade.
0.10 to 20 MeV: standards evaluation by CSEWG Standards
Committee.
MT=19 (n,f) first-chance fission cross section.
Ratio of first-chance to total fission obtained from GNASH
calculations.
MT=20 (n,nf) second-chance fission cross section.
Ratio of second-chance to total fission obtained from GNASH
calculations.
MT=21 (n,2nf) third-chance fission cross section.
Ratio of third-chance to total fission obtained from
GNASH calculations.
MT=37 GNASH Hauser-Feshbach statistical/preequilibrium calc.
MT=38 (n,3nf) fourth-chance fission cross section.
MT=51,52,54,55,57,58,60-62,64-72,74-76 Threshold to 6.0 MeV,
compound-nucleus reaction theory calculations with
width fluctuation corrections using the COMNUC code.
MT=53,56,59,63 Thr. to 20 MeV, coupled-channel optical model
calculations (9/2-, 11/2-, 13/2-, 15/2- members of the
ground-state rotational band), plus compound-nucleus
contributions from COMNUC calculations.
MT=73,77-84 Threshold to 20 MeV, distorted wave Born approx-
imation calculations with DWUCK code. These levels are
composites of l=2 and l=3 vibrational states. The l=2
states are MT=78-80,82 and the l=3 states are MT=73,77,
81,83,84.
MT=91 GNASH Hauser-Feshbach statistical/preequilibrium calc.
Note that the MT=77-84 vibrational states lie in the
MT=91 continuum region.
MT=102 2.25 to 1000 keV capture is based on newer alpha
measurements (see ANL-83-4 supplement) and fission from
Standards Committee recomendations. Most of the
structure below 100 keV is from fission. 1-20 MeV is
based on renormalized COMNUC/GNASH calculation, with a
semi-direct component added above a few MeV.
File 4 NEUTRON ANGULAR DISTRIBUTIONS ---------------------------
MT=2 Elastic scattering angular distribution based on ECIS
coupled-channel calculations, with a compound elastic
component from COMNUC included below 6 MeV.
MT=51,52,54,55,57,58,60-62,64-72,74-76 Threshold to 6.0 MeV,
compound-nucleus reaction theory calculations with width
fluctuation corrections using the COMNUC code.
MT=53,56,59,63 Thr. to 20 MeV, coupled-channel optical model
calculations (9/2-, 11/2-, 13/2-, 15/2- members of the ground-
state rotational band), plus compound-nucleus contributions
from COMNUC calculations.
MT=73,77-84 Threshold to 20 MeV, Distorted wave Born approx-
imation calculations with DWUCK code.
File 5 NEUTRON ENERGY DISTRIBUTIONS ----------------------------
MF=18 Composite neutron energy distributions from fission.
Based on calculations by D.Madland [Ma88] using Madland-Nix
formalism. The calculations include the first-, second-, and
third-chance fission neutron components. The calculations end
at 15 MeV; the 20-MeV spectrum is simply a duplication of the
15-MeV spectrum. Tabulated distribution law (LF=1) is used.
MT=455 England [En89]
File 6. CORRELATED ENERGY-ANGLE DISTRIBUTIONS ------------------
MT=16 GNASH Hauser-Feshbach statistical/preequilibrium calc.
Neutron distributions only.
MT=17 GNASH Hauser-Feshbach statistical/preequilibrium calc.
Neutron distributions only.
MT=37 GNASH Hauser-Feshbach statistical/preequilibrium calc.
Neutron distributions only.
MT=91 GNASH Hauser-Feshbach statistical/preequilibrium calc.
Neutron distributions only.
----------------------------------------------------------------
REFERENCES
[Ar88] E.D. Arthur, Los Alamos National Laboratory report
LA-UR-88-382 (1988)
[Bo72] K. Boeckhoff et al., J.Nuc.En. 26, 91 (1972)
[Br58] A. Bratenahl et al., Phys.Rev. 110, 927 (1958)
[Ca73] J. Cabe et al., report CEA-R-4524 (1973)
[Du70] C.L. Dunford, report AI-AEC-12931 (1970)
[En89] T.R. England et al, Los Alamos National Laboratory
reports LA-11151-MS(88), LA-11534T(89); LAUR-88-4118 to be
published in Nucl.Sci.Eng. (1989)
[Fo71] D. Foster and D. Glasgow, Phys.Rev. C 3, 576 (1971)
[Fr86] J. Frehaut, report NEANDC(E) 238/L (1986)
[Gr73] L. Green et al., report USNDC-9 (1973) p.170
[He80] D. Hetrick and C.Y. Fu, Oak Ridge National Laboratory
report ORNL/TM-7341 (1980)
[Ku70] P.D. Kunz, "DWUCK: A Distorted-Wave Born Approximation
Program," unpublished report
[Ma88] D.G.Madland, Nuclear Data for Science and Technology,
Proc. Int. Conf., Mito, Japan, May 30-June 3, 1988, Mito,
Japan. (Saikon Publishing, 1988) p.759
[Pe60] J. Peterson et al., Phys.Rev. 120, 521 (1960)
[Pe69] R.J. Peterson, Ann.Phys. 53, 40 (1069)
[Po81] W. Poenitz et al., Nuc.Sci.Eng. 78, 333 (1981)
[Po83] W. Poenitz et al., Argonne National Laboratory report
ANL-NDM-80 (1983)
[Ra70] J. Raynal, report IAEA SMR-9/8 (1972) p.281
[Sc74] R. Schwartz et al., Nuc.Sci.Eng. 54, 322 (1974)
[Ut66] C. Uttley et al., Paris Conf. (1966) v1, p165
[Ve80] V. Vertebnyj et al., report YFI-16,8(1973)
[Wh65] W. Whalen et al., Argonne National Laboratory report
ANL-7110 (1965) p.15
[Yo77] P.G. Young and E.D. Arthur, Los Alamos National
Laboratory report LA-6947 (1977).
[Yo88] P.G. Young and E.D. Arthur, Nuclear Data for Science and
Technology, Proc. Int. Conf., Mito, Japan, May 30-June 3,
1988, Mito, Japan. (Saikon Publishing, 1988) p.603
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