14-Si- 30 TIT,JAERI EVAL-MAR88 H.KITAZAWA,Y.HARIMA,T.FUKAHORI
DIST-JAN09 20090105
----JEFF-311 MATERIAL 1431
-----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
88-03 New evaluation was performed for JENDL-3 by Kitazawa,
Harima (Tokyo Institute of Tech.) and Fukahori (jaeri).
Details are given in ref./1/.
88-03 Compiled by fukahori.
94-01 JENDL-3.2.
Compiled by T.Nakagawa (ndc/jaeri)
***** Modified parts for JENDL-3.2 ********************
(3,2) Effects of modification of inelastic
scattering cross sections.
(3,4), (3,51-69) Cross-section curves were smoothed.
(4,16-28), (4,91) Taken from JENDL fusion file
(5,16-91) Taken from JENDL fusion file
(12,102) Below 2 mev.
***********************************************************
-------------------------------------------------------------
JENDL fusion file /2/ (as of Jan. 1994)
Evaluated and compiled by S.Chiba (ndc/jaeri)
Cross sections, angular distributions and energy distri-
butions were taken from JENDL-3.1. mf=6 of mt=16, 22, 28,
and 91 were created by f15tob program/2/ by using Kumabe's
systematics/3/. The precompound/compound ratio was taken
from the sincros-II calculation/4/.
Optical-model, level density and other parameters used
in the sincros-II calculation are described in ref./4/.
-------------------------------------------------------------
00-12 JENDL-3.3
Compiled by K.Shibata (jaeri)
***** Modified parts for JENDL-3.3 **********************
(1,451) Updated.
(3,203),(3,207) Calculated.
(3,251) Deleted.
(4,2) Transformation matrix deleted.
(4,16),(4,22) Deleted.
(4,28),(4,91) Deleted.
(5,16-91) Deleted.
(6,16-91) Taken from JENDL fusion file.
(6,203),(6,207) Taken from JENDL fusion file.
***********************************************************
mf=1 General information
mt=451 Descriptive data and dictionary
mf=2 Resonance parameters:
mt=151
Resolved resonances : 1.0e-5 eV - 0.5 MeV
The resonance parameters were searched, using MLBW formula.
An initial guess of the parameters was taken from ref./5/.
calculated 2200-m/s cross sections and resonance integrals
2200-m/sec res. integ.
elastic 2.491 b -
capture 0.108 b 0.709 b
total 2.598 b -
mf=3 Neutron cross sections
mt=1 Total cross section
Above 0.5 MeV, the cross sections were calculated with the
statistical-model code casthy./1,6/
mt=2 Elastic scattering cross sections
Obtained by subtracting partial cross sections from the total
cross sections.
mt=4,51-69,91 Inelastic scattering cross sections
Calculated with the statistical-model code casthy /6/ and the
coupled-channel model code ecis /7/, taking account of
competitive processes for neutron, proton, alpha-particle and
gamma-ray emission./1/ Below 11 MeV, the imaginary potential
strength of the neutron spherical optical potential was
modified from that in ref./1/ to be W = 1.09 + 0.55*E (MeV).
Level scheme was taken from ref./8/.
no. energy(MeV) spin-parity
g.s. 0.0 0 +
1. 2.2355 2 +
2. 3.4982 2 +
3. 3.7696 1 +
4. 3.7877 0 +
5. 4.8090 2 +
6. 4.8305 3 +
7. 5.2300 3 +
8. 5.2790 4 +
9. 5.3720 0 +
10. 5.4876 3 -
11. 5.6130 2 +
12. 5.9500 4 +
13. 6.5030 4 -
14. 6.5370 2 +
15. 6.6340 2 -
16. 6.6400 0 +
17. 6.7447 1 -
18. 6.8650 2 -
19. 6.9140 2 +
Continuum levels were assumed above 6.999 MeV. Level density
was calculated, using the Gilbert-Cameron formula. The level
density parameters were obtained from a cumulative plot of
observed levels./1/.
For JENDL-3.2, cross sections at threshold energies of the
levels were inserted by interpolating the calculated cross
sections.
mt=16 (n,2n) cross sections
Calculated by the statistical model, using the gnash code./1,
9/ below 11 MeV, the imaginary potential strength of the
neutron spherical optical potential was modified from that in
ref./1/ to be W = 1.09 + 0.55*E (MeV).
mt=22 (n,na) cross sections
Calculated by the statistical model, using the gnash code.
optical potential for alpha-particles was determined, using
the dispersion theory./10/
mt=28 (n,np) cross sections
Calculated by the statistical model, using the gnash code.
mt=102 capture
Calculated with the statistical-model code casthy /6/ and the
direct-semidirect-model code hikari /11/. The statistical-
model calculations were normalized to 0.6 mb at 0.5 MeV.
mt=103 (n,p) cross sections
Calculated by the statistical model, using the gnash code. The
imaginary potential strength of the proton spherical optical
model was modified from that in ref./1/ to be W = 11.0 MeV
between 11 and 20 MeV and W = 8.8 + 0.2*E (MeV) below 11 MeV.
mt=107 (n,a) cross sections
Calculated by the statistical model, using the gnash code.
Optical potential for alpha-particles was determined, using
the dispersion theory./10/
mt=111 (n,2p) cross sections
Calculated by the statistical model, using the gnash code.
mt=203 Total proton production cross section
Sum of mt=28, 103 and 2*(111).
mt=207 Total alpha production cross section
Sum of mt=22 and 107.
mf=4 Angular distributions of secondary neutrons
mt=2
Calculated with the statistical-model code casthy /1,6/.
mt=51-69
Incoherent sum of the statistical model and coupled-channel
model calculations./1/ Calculated with casthy and ecis.
mf=6 Energy-angle distributions of secondary particles
mt=16,22,28,91,203,207
Taken from JENDL fusion file.
mf=12 Gamma-ray multiplicities (below 7.23453 MeV)
mt=51-69,102,107
Calculated by using the gnash code/1,9/. Multiplicities of
mt=102 were determined from energy balance.
mf=13 Gamma-ray production cross sections (above 7.23453 MeV)
mt=3
Calculated by the statistical model and coupled-channel model,
using the gnash code /9/ and the ecis /7/ code. Branching
ratios for transitions between discrete levels were taken from
ref./8/. Gamma-ray transition strength in the continuum was
calculated by the Brink-Axel giant resonance model for e1
transition and by the weisskopf single-particle model for e2
and m1 transition./1/
mf=14 Gamma-ray angular distributions
mt=3,51-69,102,107
Isotropic distribution was assumed.
mf=15 Gamma-ray spectra
mt=3,102,107
Calculated with the gnash code./1,9/
References
1) Kitazawa H. et al.: Proc. Int. Conf. Nuclear Data for Science
and Technology, Mito, 1988, p.473, (1988).
2) Chiba S. et al.: JAERI-M 92-027, p.35 (1992).
3) Kumabe I. et al.: Nucl. Sci. Eng., 104, 280 (1990).
4) Yamamuro N.: JAERI-M 90-006 (1990).
5) Mughabghab S.F. et al.: "Neutron Cross Sections, Vol. 1 Part
A", Academic Press (1981).
6) Igarasi S. and Fukahori T.: JAERI 1321 (1991).
7) Raynal J.: Computer program ecis79 for coupled-channel
calculations, 1979 (unpublished).
8) Endt P.M. and Van der Leun C.: Nucl. Phys., A310, 1 (1978).
9) Young P.G. and Arthur E.D.: LA-6947 (1977).
10) Kitazawa H. et al.: unpublished.
11) Kitazawa H.: Computer program hikari for direct-semidirect
capture calculations, 1980 (unpublished).
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