44-Ru- 96
44-Ru- 96 JNDC EVAL-MAR90 JNDC FP NUCLEAR DATA W.G.
DIST-MAY10 20091203
----JENDL-4.0 MATERIAL 4425
-----INCIDENT NEUTRON DATA
------ENDF-6 FORMAT
===========================================================
JENDL-3.2 data were automatically transformed to JENDL-3.3.
Interpolation of spectra: 22 (unit base interpolation)
(3,251) deleted, T-matrix of (4,2) deleted, and others.
===========================================================
History
90-03 New evaluation for JENDL-3 was completed by JNDC FPND
W.G./1/
09-12 JENDL-4.0.
Compiled by A.Ichihara (jaea/ndc).
***** modified parts for JENDL-4.0 *******************
(3, 1), (3, 2), (3,102)
Thermal cross sections were revised by
T.Nakagawa.
(2,151) Unresolved resonance parameters were updated.
**********************************************************
mf = 1 General information
mt=451 Comments and dictionary
mf = 2 Resonance parameters
mt=151 Resolved and unresolved resonance parameters
No resolved resonance parameters
Unresolved resonance region : 250 eV - 300 keV
The neutron strength functions, S0, S1 and S2 were calculated
with optical model code CASTHY/2/. The observed level spacing
was determined to reproduce the capture cross section
calculated with CASTHY. The effective scattering radius was
obtained from fitting to the calculated total cross section at
100 keV. The radiation width Gg was based on the systematics
of measured values for neighboring nuclides.
Typical values of the parameters at 70 keV:
S0 = 0.440e-4, S1 = 4.300e-4, S2 = 0.630e-4, Sg = 5.71e-4,
Gg = 0.150 eV, R = 6.211 fm.
The unresolved resonance parameters were recalculated using
the ASREP code/22/.
The parameters should be used only for self-shielding
calculation.
Thermal cross sections and resonance integrals at 300K(b)
-------------------------------------------------------
0.0253 eV reson. integ.(*)
-------------------------------------------------------
total 5.307
elastic 5.027
capture 0.2711 6.40
-------------------------------------------------------
(*) In the energy range from 0.5 eV to 10 MeV.
mf = 3 Neutron cross sections
The capture cross section at 0.0253 eV was determined as
0.271 b on the basis of experimental data of Halperin and
Druschel/23/. Cross section shape was assumed to be 1/v
below 250 eV so as to reproduce the resonance integral of
6.36 b/3/.
The elastic scattering cross section of 5.0 b was estimated
by assuming R=6.3 fm.
The spherical optical and statistical model
calculation was performed with CASTHY, by taking account of
competing reactions, of which cross sections were calculated
with PEGASUS/4/ standing on a preequilibrium and multi-step
evaporation model. The OMP's for neutron given in Table 1 were
determined to reproduce a systematic trend of the total cross
section by changing rso of Iijima-Kawai potential/5/. The
OMP's for charged particles are as follows:
proton = Perey/6/
alpha = Huizenga and Igo/7/
deuteron = Lohr and Haeberli/8/
helium-3 and triton = Becchetti and Greenlees/9/
Parameters for the composite level density formula of Gilbert
and Cameron/10/ were evaluated by Iijima et al./11/ More
extensive determination and modification were made in the
present work. Table 2 shows the level density parameters used
in the present calculation. Energy dependence of spin cut-off
parameter in the energy range below E-joint is due to Gruppelaar
/12/.
mt = 1 Total
Spherical optical model calculation was adopted.
mt = 2 Elastic scattering
Calculated as (total - sum of partial cross sections).
mt = 4, 51 - 91 Inelastic scattering
Spherical optical and statistical model calculation was
adopted. The level scheme was based on Evaluated Nuclear
Structure Data File (1987 version)/13/ and Nuclear Data
Sheets/14/.
no. energy(MeV) spin-parity dwba cal.
gr. 0.0 0 +
1 0.8326 2 + *
2 1.5180 4 +
3 1.9311 2 +
4 2.1487 0 +
5 2.1496 6 +
6 2.2839 2 +
7 2.4621 2 +
8 2.5247 2 +
9 2.5290 2 +
10 2.5762 2 +
11 2.5882 5 -
12 2.6513 2 +
13 2.7399 1 +
Levels above 2.76 MeV were assumed to be overlapping.
For the levels with an asterisk, the contribution of direct
inelastic scattering cross sections was calculated by the
DWUCK-4 code/15/. Deformation parameter (beta2 = 0.158) was
based on the data compiled by Raman et al./16/
mt = 102 Capture
Spherical optical and statistical model calculation with
CASTHY was adopted. Direct and semi-direct capture cross
sections were estimated according to the procedure of Benzi
and Reffo/17/ and normalized to 1 milli-barn at 14 MeV.
The gamma-ray strength function (5.43e-04) was adjusted to
reproduce the capture cross section of 315 milli-barns at 25
keV measured by Sriramachandra et al./18/
mt = 16 (n,2n) cross section
mt = 22 (n,n'a) cross section
mt = 28 (n,n'p) cross section
mt = 32 (n,n'd) cross section
mt =103 (n,p) cross section
mt =104 (n,d) cross section
mt =105 (n,t) cross section
mt =106 (n,he3) cross section
mt =107 (n,alpha) cross section
mt =111 (n,2p) cross section
These reaction cross sections were calculated with the
preequilibrium and multi-step evaporation model code PEGASUS.
The Kalbach's constant k (= 118.0) was estimated by the
formula derived from Kikuchi-Kawai's formalism/19/ and level
density parameters.
Finally, the (n,p) and (n,alpha) cross sections were
normalized to the following values at 14.5 MeV:
(n,p) 150.00 mb (recommended by Forrest/20/)
(n,alpha) 31.90 mb (systematics of Forrest/20/)
The (n,2n) cross section was determined by eye-guiding of
the data measured by Bormann et al./21/
mt = 251 mu-bar
Calculated with CASTHY/2/.
mf = 4 Angular distributions of secondary neutrons
Legendre polynomial coefficients for angular distributions are
given in the center-of-mass system for mt=2 and discrete inelas-
tic levels, and in the laboratory system for mt=91. They were
calculated with CASTHY. Contribution of direct inelastic
scattering was calculated with DWUCK-4. For other reactions,
isotropic distributions in the laboratory system were assumed.
mf = 5 Energy distributions of secondary neutrons
Energy distributions of secondary neutrons were calculated with
PEGASUS for inelastic scattering to overlapping levels and for
other neutron emitting reactions.
TABLE 1 NEUTRON OPTICAL POTENTIAL PARAMETERS
DEPTH (MEV) RADIUS(FM) DIFFUSENESS(FM)
---------------------- ------------ ---------------
V = 47.5 R0 = 5.972 A0 = 0.62
WS = 9.74 RS = 6.594 AS = 0.35
VSO= 7.0 RSO= 5.97 ASO= 0.62
THE FORM OF SURFACE ABSORPTION PART IS DER. WOODS-SAXON TYPE.
TABLE 2 LEVEL DENSITY PARAMETERS
NUCLIDE SYST A(1/MEV) T(MEV) C(1/MEV) EX(MEV) PAIRING
---------------------------------------------------------------
42-MO- 92 1.064E+01 7.770E-01 2.062E-01 5.938E+00 2.210E+00
42-MO- 93 1.125E+01 7.800E-01 9.792E-01 5.457E+00 1.280E+00
42-MO- 94 1.301E+01 6.850E-01 3.417E-01 5.770E+00 2.000E+00
42-MO- 95 1.360E+01 7.150E-01 1.847E+00 5.835E+00 1.280E+00
43-TC- 93 * 9.672E+00 6.989E-01 3.869E-01 3.036E+00 9.300E-01
43-TC- 94 * 1.062E+01 6.915E-01 2.121E+00 2.589E+00 0.0
43-TC- 95 * 1.159E+01 6.842E-01 1.101E+00 3.745E+00 7.200E-01
43-TC- 96 1.741E+01 5.640E-01 1.503E+01 3.650E+00 0.0
44-RU- 94 * 9.776E+00 6.915E-01 6.034E-02 4.294E+00 2.210E+00
44-RU- 95 1.358E+01 6.720E-01 1.120E+00 5.133E+00 1.280E+00
44-RU- 96 1.343E+01 6.680E-01 3.373E-01 5.719E+00 2.000E+00
44-RU- 97 1.510E+01 6.390E-01 1.567E+00 5.300E+00 1.280E+00
---------------------------------------------------------------
syst: * = ldp's were determined from systematics.
Spin cutoff parameters were calculated as 0.146*sqrt(a)*a**(2/3).
In the CASTHY calculation, spin cutoff factors at 0 MeV were
assumed to be 5.586 for Ru- 96 and 5.0 for Ru- 97.
References
1) Kawai, M. et al.: Proc. Int. Conf. on Nuclear Data for Science
and Technology, Mito, p. 569 (1988).
2) Igarasi, S.: J. Nucl. Sci. Technol., 12, 67 (1975).
3) S.F.Mughabghab: "Atlas of Neutron Resonances," Elsevier
(2006).
4) Iijima, S. et al.: JAERI-M 87-025, p. 337 (1987).
5) Iijima, S. and Kawai, M.: J. Nucl. Sci. Technol., 20, 77
(1983).
6) Perey, F.G: Phys. Rev. 131, 745 (1963).
7) Huizenga, J.R. and Igo, G.: Nucl. Phys. 29, 462 (1962).
8) Lohr, J.M. and Haeberli, W.: Nucl. Phys. A232, 381 (1974).
9) Becchetti, F.D., Jr. and Greenlees, G.W.: Polarization
Phenomena in Nuclear Reactions ((Eds) H.H. Barshall and
W. Haeberli), p. 682, the University of Wisconsin Press.
(1971).
10) Gilbert, A. and Cameron, A.G.W.: Can. J. Phys., 43, 1446
(1965).
11) Iijima, S., et al.: J. Nucl. Sci. Technol. 21, 10 (1984).
12) Gruppelaar, H.: ECN-13 (1977).
13) ENSDF: Evaluated Nuclear Structure Data File (June 1987).
14) Nuclear Data Sheets, 35, 281 (1982).
15) Kunz, P.D.: private communication.
16) Raman, S., et al.: Atom. Data and Nucl. Data Tables 36, 1
(1987)
17) Benzi, V. and Reffo, G.: CCDN-NW/10 (1969).
18) Sriramachandra Murty, M. et al.: J. Phys. Soc. Japan, 35, 8
(1973).
19) Kikuchi, K. and Kawai, M.: "Nuclear Matter and Nuclear
Reactions", North Holland (1968).
20) Forrest, R.A.: AERE-R 12419 (1986).
21) Bormann, M., et al.: Nucl. Phys., A157, 481 (1970)
22) Y.Kikuchi et al., JAERI-Data/Code 99-025 (1999)
[in Japanese].
23) J.Halperin, R.E.Druschel: ORNL 3832, p.5 (1965).