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74-W -183 KHI,NEDAC EVAL-MAR87 T.WATANABE(KHI), T.ASAMI(NEDAC)
DIST-JAN09 20090105
----JEFF-311 MATERIAL 7434
-----INCIDENT NEUTRON DATA
------ENDF-6 FORMAT
*************************** JEFF-3.1.1 *************************
** **
** Original data taken from: JEFF-3.1 **
** **
******************************************************************
***************************** JEFF-3.1 *************************
** **
** Original data taken from: JENDL-3.3 **
** **
******************************************************************
HISTORY
87-03 New evaluation was made for JENDL-3.
94-01 JENDL-3.2.
Compiled by T.Nakagawa (ndc/jaeri)
00-03 Reevaluation was made by T.Asami.
01-11 Compiled by K.Shibata (ndc/jaeri)
***** modified parts for JENDL-3.3 from JENDL-3.2 ******
(3,2)
(3,16,28) revised
(3,203,207) added
(3,251) deleted
(4,2) transformation matrix deleted
(4,16,17,22,28,91) deleted
(5,16,17,22,28,91) deleted
(6,16,17,22,28,91) taken from JENDL fusion file
(6,203,204,207) taken from JENDL fusion file
(12,22-107) evaluated newly
(13,3) evaluated newly
(14,3-107) isotropic distributions
(15,3-107) evaluated newly
***********************************************************
The JENDL fusion file /1/ and the modification of JENDL-3.2
from JENDL-3.1 as follows:
-------------------------------------------------------------
JENDL fusion file /1/ (as of Jan. 1994)
Evaluated by K.Kosako (nedac) and S.Chiba (ndc/jaeri)
Compiled by K.Kosako.
Data were taken from JENDL-3.1 except for the following:
- The inelastic scattering cross sections to cotinuum
(mt=91) was calculated with casthy2y and dwucky in
sincros-ii system/2/ including contributions from direct
reactions.
- The (n,2n), (n,3n), (n,na), (n,np), (n,p), (n,d) and
(n,a) reaction cross sections (mt=16, 17, 22, 28, 103,
104, 107) were calculated by egnash2 in the sincros-ii.
- Energy distributions of secondary neutrons were replaced
by those calculated by egnash2. The ddx's of the
continuum neutrons were calculated by Kumabe's systema-
tics /3/ using f15tob /1/. The precompound/compound
ratio was calculated by the sincros- ii code system.
- Optical-model, level density and other parameters used in
the sincros-ii calculation are described in ref./2/.
Level schemes were determined on the basis of ENSDF/4/.
-------------------------------------------------------------
mf=1 General information
mt=451 Descriptive data and dictionary
mf=2 Resonance parameters
mt=151 Resolved resonance parameters
Resolved parameters for MLBW formula were given in the energy
region from 1.0e-5 eV to 2.2 keV. Parameters were evaluated by
examining both the experimental data/5,6,7/ and the recommended
data of BNL/8/. For unknown radiative width, an average value
of 55 milli-ev was assumed. Parameters for a negative
resonance were selected so that the 2200 m/s cross section for
capture reproduced gave a recommended value of 10.2 barns/8/
and gave a good fit to the experimental data for total cross
sections around thermal energies. The scattering radius was
assumed to be 7.3 fm. Calculated 2200 m/sec cross sections and
resonance integrals are as follows:
2200 m/s cross section(b) res. integral(b)
elastic 2.38
capture 10.11 335.
total 12.49
mf=3 Neutron cross sections
Below 2.2 keV, zero background cross section was given and all
the cross-section data are reproduced from the evaluated
resonance parameters with MLBW formula.
For JENDL-3.1, above 2.2 keV, the total and partial cross
sections were given mainly based on the theoretical calcula-
tions. the total, elastic and inelastic scattering, and capture
cross sections were calculated with the coupled-channel model
and the spherical optical-statistical model. The calculations
were performed with a combined program of casthy/9/ and ecis
/10/. the spherical optical potential parameters used are:
V = 48.83 - 0.0809*En, Vso = 5.6 (MeV)
Ws = 6.73 - 0.0536*En, Wv = 0 (MeV)
r = 1.168, rs = 1.268, rso = 1.592 (fm)
a = 0.617, aso = 0.664, b = 0.563 (fm)
The deformed potential parameters were taken from the work of
Delaroche/11/.
mt=1 Total
Calculated with the combined program of the ecis and casthy
codes. Almost the same as JENDL-3.1.
mt=2 Elastic scattering
Obtained by subtracting the sum of the partial cross sections
from the total cross section.
mt=4, 51-60, 91 Inelastic scattering
The data of mt=51 to 60 were calculated with the combined
program of casthy /9/ and ecis/10/. These cross sections
are the same as JENDL-3.1 except that new calculation
was made at additional several energy points. The cross
section of mt=91 was calculated with sincros-ii for JENDL
fusion file. The level scheme was based on ref./4/
Contributions of the direct process were calculated for the
levels marked with '*'.
no. mt energy(MeV) spin-parity (direct process)
g.s. 0.0 1/2 -
1 51 0.0465 3/2 - *
2 52 0.0991 5/2 - *
3 53 0.2070 7/2 - *
4 54 0.2088 3/2 -
5 55 0.2917 5/2 -
6 56 0.3089 9/2 - *
7 57 0.3095 11/2 +
8 58 0.4121 7/2 -
9 58 0.4530 7/2 -
10 59 0.4870 13/2 +
11 59 0.5330 1/2 +
12 60 0.5500 9/2 -
13 60 0.5953 9/2 -
14 60 0.6228 9/2 +
Levels above 0.624 MeV were assumed to be overlapping. Data of
levels 8-9, 10-11 and 12-14 were lumped as is indicated in the
above table. The direct inelastic scattering cross section was
calculated also for the levels at 0.904, 0.935, 1.025, 1.485,
1.866, 2.127, 2.505, 2.912, 3.404, 4.0, 4.5, 5.0 and 5.5 MeV,
and added to mt=91.
Finally, the data for mt=51,52,54,55,57,58 and 91 were adjusted
to reproduce the benchmark integral data/16/.
mt=16, 28 (n,2n), (n,np)
calculated with the scincros-ii system/2/.
mt=17, 22, 103, 104, 107
(n,3n), (n,na), (n,p), (n,d), (n,a)
Theoretical calculation was made with sincros-ii. The
results were normalized to
(n,p) 0.0041 b at 14.7 MeV measured by Qaim/17/,
(n,d)+(n,np) 0.0013 b at 14.7 MeV measured by Qaim/17/,
(n,a) 0.0018 b at 14.7 MeV (systematics of Qaim/17/).
mt=102 capture
Calculated with the casthy code/9/ and normalized to 70+-9 mb
at 500 kev/18/. Above 3 MeV, a straight line in log-log scale
was adopted assuming 1.0 mb at 14 MeV for JENDL-3.2.
mt=203 Total proton production
Sum of mt=28 and 103.
mt=204 Total deuteron production
Equal to mt=104.
mt=207 : total alpha production
Sum of mt=22 and 107.
mf=4 Angular distributions of secondary neutrons
(mt=2, 51-60: the same as JENDL-3.1)
mt=2
Calculated with the casthy code/9/.
mt=51-60
Calculated with the combined program of casthy/9/ and
ecis/10/ codes.
mf=6 Energy-angle distributions of secondary particles
mt=16, 17, 22, 28, 91
Based on Kumabe's systematics/1,3/.
mt=203,204,207
Based on Kalbach's systematics/1,19/.
mf=12 Photon production multiplicities and transition probability
arrays
mt=22, 51-60,102,103,107
Below 627.44 keV, given as multiplicities
Calculated with the egnash code/2/ and processed by
the gamfil2 code/20/.
mt=102 was calculated with the casthy code/10/.
mf=13 Photon production cross sections
mt=3
Calculated with the egnash code/2/ and processed by the
gamfil2 code/20/.
mf=14 Photon angular distributions
mt=3, 22, 51-60, 102, 103, 107
Assumed to be isotropic distributions
mf=15 Continuous photon energy spectra
mt=3, 22, 103, 107
Calculated with the egnash code/2/.
mt=102
Calculated with the casthy code/10/.
References
1) Chiba, S. et al.: JAERI-M 92-027, p.35 (1992).
2) Yamamuro, N.: JAERI-M 90-006 (1990).
3) Kumabe, I. et al.: Nucl. Sci. Eng., 104, 280 (1990).
4) ENSDF: Evaluated Nuclear Structure Data File, BNL/NNDC.
5) Camarda H.S. et al. : Phys. Rev. C8, 1813 (1973).
6) Ohkubo M. : JAERI-M 5624 (1974).
7) Macklin R.L. et al. : LA-9200-MS (1982).
8) Mughabghab S.f. :"Neutron Cross Sections", Vol. 1, part B
(1984).
9) Igarasi S. and Fukahori T.: JAREI 1321 (1991).
10) Raynal J. : IAEA-SMR-9/8 p.281 (1972).
11) Delaroche J.F. et al. : 1979 Knoxville Conf. 336 (1979).
12) Perey F.G.: Phys. Rev., 131, 745 (1963).
13) Arthur, E.D. and Young, P.G.: LA-8626-MS (1980).
14) Lohr J.M. and Haeberli W.: Nucl. Phys., A232, 381 (1974).
15) Becchetti F.D. Jr. and Greenlees G.W.: "Polarization
Phenomena in Nucl. Reactions," Univ. Wisconsin Press, p.682
(1971).
16) Oyama, Y. et al.: JAERI-CONF 96-005, 70(1996).
17) Qaim,S.M. and Graca, C.: Nucl. Phys., A242, 317 (1975).
18) Voignier J. et al.: Nucl. Sci. Eng., 93, 43 (1986).
19) Kalbach C. : Phys. Rev. C37, 2350(1988).
20) Hida K.: JAERI-M 86-150 (1986) (in Japanese).
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