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79-Au-197 LANL EVAL-JAN84 P.G.YOUNG
LA-10069-PR DIST-JAN09 20090105
----JEFF-311 MATERIAL 7925
-----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 *************************
** **
** Original data taken from: JEFF-3.0 **
** **
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***************************** JEFF-3.0 ***********************
DATA TAKEN FROM :- ENDF/B-VI rel.4 (DIST-SEPT91 REV1-JUL91)
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MOD1 OF ENDF/B-VI
The following revisions were made for MOD1 of ENDF/B-VI:
1. MF=1,MT=451 - Comments were added regarding estimated
(expanded) covariance for the Standards Cross Sections.
2. MF=3,MT=102 - Q-value corrected.
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*************** SUMMARY OF ENDF/B-VI EVALUATION ******************
A new evaluation of all neutron and gamma-ray data above the
resonance region is joined with the endf/b-v resolved resonance
region evaluation and with the Version VI standard cross section
for the (n,gamma) reaction below a neutron energy of 2.5 MeV.
*************** GENERAL DESCRIPTION ******************************
P.G.Young and E.D.Arthur
the new evaluation for files 3,4,5,12,13,14,15 is based on
statistical theory, hauser-feshbach, preequilibrium calculations
with the comnuc and gnash codes (ref1,2). deformed optical poten-
tial of delaroche and ecis coupled-channel code were used to cal-
culate neutron transmission coefficients and total and elastic
elastic cross sections (ref3,4). gamma-ray strength functions
were obtained by fitting morgan n,xg data (ref5) at 0.4 and 6.5
mev. calculated results were used for all major reactions except
total cross section. for total, the theoretical cross section
was used as prior in covariance analysis of experimental data
using glucs code (ref6). more details on experimental data used
are given below and in main reference for evaluation (ref 7).
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STANDARDS COVARIANCES
Phase 1 reviewers of the ENDF/B-VI standards cross sections have
expressed the concern that the uncertainties resulting from the
combination of R-matrix and simultaneous evaluations might have
led to uncertainties that are too small. As a result, the
Standards Subcommittee produced (at the May, 1990 CSEWG meeting)
a set of expanded covariance estimates for the standard cross
section reactions. These uncertainties are estimates such that
if a modern day experiment were performed on a given standard
cross section using the best techniques, approximately 2/3 of
the results should fall within these expanded uncertainties. The
expanded uncertainties for the Au-197(n,gamma) cross section are
given in the following table and are compared to values from the
combined output of the standards covariance analysis:
Energy Range Estimated Uncertainty Combined Analysis
(keV) (percent) (percent)
2.53E-05 0.14 0.14
200 - 500 3.0 1.31
500 - 1000 3.5 2.1
1000 - 2500 4.5 2.0
*************** mf=2 resonance parameters ************************
mt=151 resolved resonance parameters given from 1.0e-05ev
to 2 kev based on ref8 and references therein
and a bound level. some of the reson. spin assignments
from ref9. from 2 to 4.827 kev the parameters are based
on macklin et al and hoffman et al normalized data.
see refs 10 and 11.
thermal cross sections are as follows:
capture = 98.71 b
scattering = 6.84 b
total = 105.55 b
the absorption resonance integral is 1559 b
*************** mf=3 smooth neutron cross sections ***************
mt= 1 total cross section. based on glucs covariance analysis
using deformed optical model calculation as the prior and
experimental data from refs 12-22, 29 for fitting.
mt= 2 elastic cross section. difference of mt=1 and sum of
all nonelastic cross sections. closely approximates theore-
tical results.
mt= 4 inelastic cross section. sum of mt=51-63, 91.
mt= 16 (n,2n) cross section. theoretical calculation used.
in good agreement with exp. below 23 mev. see refs 23-25.
mt= 17 (n,3n) cross section. theoretical calculation used.
in good agreement with exp. at all energies (refs 24,25).
mt= 37 (n,4n) cross section. theoretical calculation used.
in reasonable agreement with data of ref 25.
mt=51-63 (n,nprime) cross sections to levels. except for mt=53
and 56, all are from compound-nucleus calculations with the
comnuc code. mt=53 and 56 also include direct reaction com-
ponents from ecis calculations (mt53 and 56 are the 5/2+
and 7/2+ members of the ground state rotational band) and
extend to 30 mev. mt=51,52,54,55,57-63 are zeroed above 6 mev.
mt= 91 inelastic continuum cross section. from gnash theoreti-
cal calculations. includes (n,gn) component from 0.1 to
2.0 mev. conventional (n,ng) continuum starts at 1.2236
mev. q-value has no significance except corresponds to thres.
mt=102 (n,gamma) cross section. below 2.5 MeV, adopted the
ENDF/B-VI standard cross section (Ref.30,31) down to the
resonance region. At higher energies, the theoretical cal-
culations were adjusted to agree with experimental data. A
semi-direct component normalized to an average of experimental
data at 14 MeV was included above En = 6 MeV.
at higher energies, use theoretical calculations, which agree
reasonably with available exp. data. above 5 mev, calculation
includes semi-direct component normalized to average of
14 mev data.
mt=103 (n,p) cross section. adopted endf/b-v with smooth
extrapolation to 30 mev. based on exp data of ref 26.
mt=107 (n,alpha) cross section. adopted endf/b-v with smooth
extrapolation to 30 mev. based on data of ref 26.
*************** mf=4 neutron angular distributions ***************
mt= 2 elastic scattering. legendre coefficients obtained by
combining ecis direct reaction calculations with comnuc com-
pound nucleus results.
mt= 16 (n,2n) angular distribution. used kalbach-mann (ref 27)
semi-empirical shape averaged over the emitted neutron
spectrum at each incident neutron energy.
mt= 17 (n,3n) angular distribution. same comment as mt=16.
mt= 37 (n,4n) angular distribution. same comment as mt=16.
mt=51-63 (n,nprime) level angular distributions. legendre coef
-ficients obtained from comnuc compound nucleus calculations.
for mt=53 and 56, ecis direct reaction results were combined
with the compound nucleus calculations,
mt= 91 (n,nprime) continuum. same comment as for mt=16.
*************** mf=5 neutron energy distributions ****************
mt= 16 (n,2n) tabulated distribution from gnash calculations.
mt= 17 (n,3n) tabulated distribution from gnash calculations.
mt= 37 (n,4n) tabulated distribution from gnash calculations.
mt= 91 (n,nprime) continuum tabulated distribution obtained from
gnash calculation.
*************** mf=8 radioactive decay data **********************
mt= 16 decay data for the 10 hour metastable sixth excited state
in au-196. endf/b-v data adopted without change.
*************** mf=10 radioactive nuclide cross sections *********
mt= 16 production cross section for the 10-hour metastable sixth
excited state of au-196 through (n,2n) reactions. endf/b-v
data adopted, with smooth extrapolation to 30 mev.
*************** mf=12 photon multiplicities **********************
mt=102 (n,gamma) yield at low energies obtained by requiring
energy conservation with mf=15,mt=102 results. beginning
near 10 kev, gnash results used.
*************** mf=13 photon cross sections **********************
mt= 4 gamma-ray production cross sections obtained from gnash
calculations for continua regions and from comnuc for
discrete levels. ecis was used to calculate direct react-
tion contributions for 3rd and 6th levels of au-197.
mt= 16 gamma-ray production cross sections obtained from gnash
calculations at all incident neutron energies.
mt= 17 gamma-ray production cross sections obtained from gnash
calculations at all incident neutron energies.
mt= 37 gamma-ray production cross sections obtained from gnash
calculations at all incident neutron energies.
*************** mf=14 photon angular distributions ***************
mt= 4 photons from inelastic scattering assumed isotropic.
mt= 16 photons from (n,2n) reactions assumed isotropic.
mt= 17 photons from (n,3n) reactions assumed isotropic.
mt= 37 photons from (n,4n) reactions assumed isotropic.
mt=102 photons from (n,gamma) reactions assumed isotropic.
*************** mf=15 photon energy distributions ****************
mt= 4 inelastic scattering photon tabulated distributions
obtained from gnash calculations for continua regions and
from comnuc for discrete levels. direct contributions for
mt=53 and mt=56 obtained from ecis calculations.
mt= 16 (n,2n) photon tabulated distributions obtained from
gnash calculations.
mt= 17 (n,3n) photon tabulated distributions obtained from
gnash calculations.
mt= 37 (n,4n) photon tabulated distributions obtained from
gnash calculations.
mt=102 (n,gamma) tabulated thermal distribution obtained from
experimental data of ref 28. thermal spectrum linearly inter-
polated to gnash calculation at 10 kev. gnash results used
at higher energies.
*************** mf=33 neutron cross section covariances **********
mt= 1 total cross section covariance from glucs analysis.
*************** references ***************************************
1. c.l.dunford. ai-aec-12931(1970)
2. p.g.young, e.d.arthur, la-6947 (1977).
3. j.p.delaroche, harwell conference (1978)p.366.
4. j.raynal, iaea smr-9/8 (1970).
5. g.l.morgan, e.newman, ornl-tm-4973 (1975).
6. d.m.hetrick, c.y.fu, ornl/tm-7341 (1980).
7. p.g.young, e.d.arthur, in la-10069-pr (1984)p.12.
8. s.f.mughabghab and d.i.garber bnl-325,3rd edn,vol i(1973).
9. a.lottin and a.jain conf on nuclear structure study with
neutrons,budapest,1972 p34 and private communication.
10. r.macklin et al. phys. rev/c 11,1270(1975) and private
communication.
11. m.m. hoffman et al. 71knoxville conf., 2, 868(1971)
12. w.poenitz et al., nuc.sci.eng. 78, 333(1981).
13. d.g.foster jr., d.glasgow, phys.rev. c3, 576(1971).
14. k.k.seth,phys.letters,16,306(1965).
15. s.c.snowdon, phys.rev. 90, 615(1953).
16. j.f.whalen,anl-7210,16(1966).
17. n.nereson, phys.rev. 94, 1678(1954).
18. a.bratenahl et al., phys.rev. 110, 927(1958).
19. j.p.conner,phys.rev.109,1268(1958).
20. j.h.coon,phys.rev.88,562(1952).
21. j.m.peterson,phys.rev.120,521(1960).
22. e.g.bilpuch,private communication(1959).
23. j.frehaut et al, proc. 10-50 mev conf, bnl-ncs-51245 (1980)
page 399.
24. l.r.veeser et al, phys.rev. c16, 1792(1977).
25. b.p.bayhurst et al, phys.rev. c12, 451(1975).
26. r.j.prestwood and b.p.bayhurst,phys.rev.121,1438(1961).
27. c.kalbach and f.mann, bnl-ncs-5/245,p.689 (1980).
28. v.j.orphan et al, ga-10248 (1970).
29. d.c.larson, proc. 10-50 mev conf, bnl-ncs-51245 (1980) p.277.
30. A.Carlson et al., Nuc.Data for Basic & Applied Science,
Santa Fe, NM (1985) p.1429.
31. W.Poenitz, ANL-West, personnal communication (1989).
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***************** PROGRAM FIXUP (VERSION 86-2) ******************
*RECONSTRUCTED MT NUMBERS
4 =+( 51, 91)
103 =+(700,718)
104 =+(720,738)
105 =+(740,758)
106 =+(760,778)
107 =+(780,798)
101 =+(102,114)
27 =+( 18, 18)+(101,101)
3 =+( 4, 4)+( 6, 9)+( 16, 17)+( 22, 37)
19 =+( 18, 18)-( 20, 21)-( 38, 38)
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