20-Ca- 48
20-CA- 48 DEC EVAL-MAR87 M.HATCHYA(DATA ENG. CO.)
DIST-MAR02 REV3-MAY01 20010521
----JENDL-3.3 MATERIAL 2049
-----INCIDENT NEUTRON DATA
------ENDF-6 FORMAT
HISTORY
87-03 New evaluation was made to give a full revision for JENDL-2
data.
87-03 Compiled by T.Asami(nedac)
93-11 JENDL-3.2
Data were mainly adopted from JENDL fusion file.
Compiled by T.Nakagawa
***** modified parts for JENDL-3.2 ********************
(3,1), (3,2), (3,4), (3,16), (3,17), (3,28), (3,51-91),
(3,103).
(3,22), (3:53-58): deleted
all angular distributions except for (4,2).
all energy distributions.
***********************************************************
-------------------------------------------------------------
JENDL fusion file /1/ (as of Nov. 1993)
Evaluated by K.Kosako (nedac) and S.Chiba (ndc/jaeri)
Compiled by k.kosako.
- The inelastic scattering cross sections and angular
distributions of inelastically scattered neutrons (except
continuum inelastic) were calculated with casthy2y and
dwucky in sincros-ii system/2/ including contributions
from direct reactions.
- The (n,2n), (n,3n) and (n,np) reaction cross sections
(mt=16, 17, 28) were calculated by egnash2 in the
sincros-ii.
- Energy distributions of secondary neutrons were replaced
with 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.
- The resonance parameters, total, capture, (n,p) and (n,a)
cross sections and ang. distributions of elastically
scattered neutrons were taken from JENDL-3.1.
- 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/.
-------------------------------------------------------------
2001-05 JENDL-3.3
Gamma-ray production date were evaluated and compiled by
K.Shibata (jaeri/ndc).
******** modified parts for JENDL-3.3 ******************
(1,451) Updated.
(3,203), (3,207) Calculated.
(3,251) Deleted.
(4,2) Transformation matrix deleted.
(4,16-91) Deleted.
(5,16-91) Deleted.
(6,16-207) Taken form JENDL fusion file.
(12,16-107) Evaluated.
(14,16-107) Evaluated.
(15,16-107) Evaluated.
**********************************************************
mf=1 Ggeneral 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 500 keV. Parameters were taken from
the recommended data of BNL/5/ and the data for a negative
resonance were added so as to reproduce the recommended thermal
cross sections for capture and scattering/5/. The scattering
radius was assumed to be 3.6 fermi. Calculated 2200 m/sec
cross sections and resonance integrals are as follows:
2200 m/s cross section(b) res. integral(b)
elastic 3.717
capture 1.092 0.4859
total 4.809
mf=3 Neutron cross sections
Below 500 keV, zero background cross section was given and all
the cross-section data are reproduced from the evaluated
resolved resonance parameters with MLBW formula.
For JENDL-3.2, all cross-section data except for the total,
capture, (n,p) and (n,a) cross sections were adopted from JENDL
fusion file. the calculation was made with sincros-ii system
/2/ by adopting Walter-guss omp modified by Yamamuro/2/ for
neutron, Perey omp /6/ for proton, Lemos omp modified by Arthur
and Young/7/ for alpha, Lohr-Haeberli omp/8/ for deuteron,
Becchettii-Greenlees omp/9/ for triton and he-3, and standard
level density parameters of sincros-ii system.
mt=1 Total
Optical and statistical model calculation was made with the
casthy code/10/. The optical potential parameters used are:
V = 49.68, Vso = 7.12 (MeV)
Ws = 7.76 - 0.5*En, Wv = 0 (MeV)
r = 1.17, rs = 1.09, rso = 1.17 (fm)
a = 0.6, aso = 0.6, b = 0.69 (fm)
The shape of the total cross section was slightly modified
for JENDL-3.2.
mt=2 Elastic scattering
Obtained by subtracting the sum of the partial cross sections
from the total cross section.
mt=4, 51-52, 91 Inelastic scattering
The cross sections were taken from JENDL fusion file. The
level scheme was based on ref./4/ Contributions of the direct
process were calculated for the levels marked with '*' by means
of dwucky. Deformation parameters were adopted from Raman et
al./11/ and Spear/12/.
no. energy(MeV) spin-parity (direct process)
0.0 0 +
1 3.8317 2 + *
2 4.2842 0 +
Levels above 4.284 MeV were assumed to be overlapping. The
levels for mts=53 to 58 given in JENDL-3.1 were not considered
in JENDL fusion file. The direct inelstic cross section to the
levels at 4.507 mev was calculated with dwucky and added to the
continuum inelastic cross section (mt=91).
mt=16, 17, 28 (n,2n), (n,3n), (n,np)
Adopted from JENDL fusion file. Theoretical calculation was
made with sincros-ii. The (n,2n) cross section was normalized
to the experimental data of Ikeda et al./13/ (0.759 b at 13.99
MeV)
mt=103, 107 (n,p), (n,a)
Calculated with the gnash code/14/ using the optical model
parameters listed at mt=1. The (n,p) cross sections were
normalized to the experimental data of Tiwari et al./15/ at
14.5 MeV. The shape of (n,p) cross section around the threshold
energy was changed for JENDL-3.2.
mt=102 Capture
calculated with the casthy code/10/ and normalized to 1.05 mb
at 30 keV/16/.
mf=4 Angular distributions of secondary neutrons
mt=2
Calculated with the casthy code/10/.
mt=51-52
Taken from JENDL fusion file. Calculated with the casthy and
dwucky in the sincros-ii system.
mf=6 Energy-angle distributions of secondary particles
mt=16, 17, 28, 91
Based on kumabe's systematics/3/.
mt=203, 207
Based on kalbach's 1988 systematics/17/.
mf=12 Photon production multiplicities
mt=16, 28, 51-52, 91, 103, 107
Calculated with the egnash code/2/.
mt=102
Calculated with the casthy code/10/.
mf=14 Photon angular distributions
mt=16, 28, 51-52, 91, 102, 103, 107
Assumed to be isotropic in the laboratory system.
mf=15 Continuous photon energy spectra
mt=16, 28, 91, 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) Mughabghab, S.F. et al. :"Neutron Cross Sections",
Vol. 1, Part A (1981).
6) Perey, F.G.: Phys. Rev., 131, 745 (1963).
7) Arthur, E.D. and Young, P.G.: LA-8626-MS (1980).
8) Lohr, J.M. and Haeberli, W.: Nucl. Phys., A232, 381 (1974).
9) Becchetti, F.D. Jr. and Greenlees, G.W.: "Polarization
Phenomena in Nucl. Reactions," Univ. Wisconsin Press, p.682
(1971).
10) Igarasi, S. and Fukahori, T.: JAERI 1321 (1991).
11) Raman, S., et al.: Atom. Data and Nucl. Data Tables 36, 1
(1987)
12) Spear, R.H.: Atom. Data and Nucl. Data Table, 42, 55 (1989).
13) Ikeda, Y. et al.: JAERI 1312 (1988).
14) Young, P.G. and Arthur, E.D. : LA-6947 (1977).
15) Tiwari, P.N. et al. : Phys. Rev. 167, 1091 (1968).
16) Carton, R.F. et al.: Nucl. Phys., A465, 274 (1987).
17) Kalbach, C. : Phys. Rev. C37, 2350(1988).