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67-Ho-165 LANL EVAL-APR88 P.G.YOUNG AND E.D.ARTHUR
DIST-JAN09 20090105
----JEFF-311 MATERIAL 6725 REVISION 1
-----INCIDENT NEUTRON DATA
------ENDF-6 FORMAT
*************************** JEFF-3.1.1 *************************
** **
** Original data taken from: JEFF-3.1 **
** **
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***************************** JEFF-3.1 *************************
** **
** Original data taken from: ENDF/B-VI.8 **
** **
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ENDF/B-VI MOD 2 Revision, August 1997, V. McLane (NNDC)
MF=1; MT=451 Update of comments.
MF=2; MT=151 Corrected total and neutron width for 8.16 eV
resonance.
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ENDF/B-VI MOD 1 Evaluation, April 1988, P.G.Young and
E.D. Arthur (LANL)
MF=2 RESONANCE PARAMETERS
MT=151 Resolved resonance range 1.0E-5 to 151.92 eV.
Resonance parameters of Mughabghab [Mu73] taken from
ENDF/B-V evaluation of Schenter and Schmittroth
2200 m/s capture cross section (barns)
(from resonance parameters) = 20.7446 b
(from 1/v component) = 43.9554 b
Total = 64.700 b
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ENERGY RANGE ABOVE THE RESONANCE REGION.
The evaluation above 10 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 contributions. Systematics were used
to obtain parameters for the exciton preequilibrium model, with
small adjustments made to improve agreement with available
experimental data.
The Gilbert-Cameron level density model was used
to supplement available experimental information on low-lying
levels [Gi65].
The Brink-Axel model [Br55],[Ax62] was used to calculate
gamma-ray transmission coefficients, using gamma-ray strength
function results compiled by Mughabghab [Mu84].
A description of the calculations is given in [Yo86].
MF=3 SMOOTH CROSS SECTIONS
MT=1 Neutron Total Cross Section. 0.01 to 30 MeV, based on
coupled-channel optical calculations, which were optimized
to the available experimental data [Mc88].
MT=2 0.030 to 30 MeV, based on subtraction of MT=4,16,17,37,
and 102 from MT=1. Note that this corresponds exactly to
using the results of the coupled-channel optical and
Hauser-Feshbach model results.
MT=4 Sum of MT=51-91
MT=16 GNASH Hauser-Feshbach statistical/preequilibrium calc.
MT=17 GNASH Hauser-Feshbach statistical/preequilibrium calc.
MT=37 GNASH Hauser-Feshbach statistical/preequilibrium calc.
MT=51,52 Threshold to 30 MeV, Coupled-channel optical model
calculations plus compound-nucleus contributions.
MT=53-63 Threshold to 8.0 MeV, Compound nucleus reaction
theory calculations using the COMNUC code [Du70] and
including width fluctuation corrections. Transmission
coefficients from c-c optical model calculations used.
MT=91 GNASH Hauser-Feshbach statistical/preequilibrium calc.
MT=102 GNASH Hauser-Feshbach statistical/preequilibrium calc.
MF=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 8 MeV.
MT=16 (n,2n) distributions assumed isotropic in laboratory
system.
MT=17 (n,3n) distributions assumed isotropic in laboratory
system.
MT=37 (n,4n) distributions assumed isotropic in laboratory
system.
MT=51,52 Threshold to 30 MeV, Coupled-channel optical model
calculations plus compound-nucleus contributions.
MT=53-63 Threshold to 8.0 MeV, Compound nucleus reaction
theory calculations using the COMNUC code [Du70] and
including width fluctuation corrections. Transmission
coefficients from cc optical model calculations used.
MT=91 (n,n'continuum) distributions assumed isotropic in the
laboratory system.
MF=5 NEUTRON ENERGY DISTRIBUTIONS
MT=16 GNASH Hauser-Feshbach statistical/preequilibrium
calculation. Tabulated laboratory distributions given.
MT=17 GNASH Hauser-Feshbach statistical/preequilibrium
calculation. Tabulated laboratory distributions given.
MT=37 GNASH Hauser-Feshbach statistical/preequilibrium
calculation. Tabulated laboratory distributions given.
MT=91 GNASH Hauser-Feshbach statistical/preequilibrium
calculation. Tabulated laboratory distributions given.
MF=12 PHOTON MULTIPLICITIES
MT=102 GNASH Hauser-Feshbach statistical/preequilibrium
calculation. Note that photons from (n,gn') reactions are
included in MF=12,MT=102 but not in MF=3,MT=102, which
causes the multiplicities at higher energies to become
somewhat large.
MF=13 PHOTON PRODUCTION CROSS SECTIONS
MT=4 GNASH Hauser-Feshbach statistical/preequilibrium
calculation.
MT=16 GNASH Hauser-Feshbach statistical/preequilibrium
calculation.
MT=17 GNASH Hauser-Feshbach statistical/preequilibrium
calculation.
MT=37 GNASH Hauser-Feshbach statistical/preequilibrium
calculation.
MF=14 PHOTON ANGULAR DISTRIBUTIONS
MT=4 Isotropy assumed.
MT=16 Isotropy assumed.
MT=17 Isotropy assumed.
MT=37 Isotropy assumed.
MT=102 Isotropy assumed.
MF=15 PHOTON ENERGY DISTRIBUTIONS
MT=4 GNASH Hauser-Feshbach statistical/preequilibrium
calculation.
MT=16 GNASH Hauser-Feshbach statistical/preequilibrium
calculation.
MT=17 GNASH Hauser-Feshbach statistical/preequilibrium
calculation.
MT=37 GNASH Hauser-Feshbach statistical/preequilibrium
calculation.
MT=102 GNASH Hauser-Feshbach statistical/preequilibrium
calculation.
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REFERENCES
[Ar88] E.D. Arthur, Los Alamos preprint LA-UR-88-382 (1988)
[Ax62] P. Axel, Phys.Rev. 126, 671 (1962)
[Br55] D.M. Brink, D.Ph.Thesis, Oxford (1955)
[Du70] C.L. Dunford, Atomics Int. report, AI-AEC-12931 (1970)
[Mc88] V. McLane et al., Neutron Cross Sections, Vol.2
(Academic Press, 1988)
[Mu73] S.F. Mughabghab and D.I. Garber, BNL-325, 3 Ed.,Vol.1
(1973)
[Mu84] S.F. Mughabghab, Neutron Cross Sections, Vol.1, Part B
(Academic Press, 1986)
[Ra70] J. Raynal, IAEA report IAEA SMR-9/8 (1970)
[Yo77] P.G. Young and E.D. Arthur, Los Alamos National Lab.
report LA-6947 (1977)
[Yo86] P.G. Young, Los Alamos National Lab. report LA-10689-PR
(1986) p.53
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