37-Rb- 85 JAEA EVAL-AUG09 K.Shibata, A.Ichihara, S.Kunieda
DIST-MAY10 20091118
----JENDL-4.0 MATERIAL 3725
-----INCIDENT NEUTRON DATA
------ENDF-6 FORMAT
History
09-08 Evaluated by K. Shibata, A. Ichihara and S. Kunieda.
09-10 Compiled by K. Shibata.
MF= 1 General information
MT=451 Descriptive data and directory
MF= 2 Resonance parameters
MT=151 Resolved and unresolved resonance parameters
Resolved resonance region (MLBW formula) : below 8.468 keV
Resonance parameters of JENDL-2 were modified as follows :
Evaluation of JENDL-2 was performed on the basis of the data
measured by Ohkubo et al./1/ among 138 levels measured in
the energy region up to 18.6 keV, 116 resonance levels were
assumed to be s-wave, and remaining 22 levels were estimated
to be p-wave. Neutron widths of all levels were determined
from the 2g*(neutron width) measured by Ohkubo et al.
However, the value of total spin J for each resonance level
was unknown except 13 levels assigned by Ohkubo et al., and
the target spin of 2.5 was adopted as J for J-unknown
levels. Radiation widths were obtained for 10 levels below
2.6 keV from the measurement by Ohkubo et al. Average
radiation width was also estimated to be 328+-18 meV by
Ohkubo et al., and was adopted for the other levels. A
negative resonance was added at -943 eV so as to reproduce
the thermal capture cross section of 480+-10 mb given by
Mughabghab et al./2/
For JENDL-3, the total spin J of 125 resonance levels was
tentatively estimated with a random number method. Neutron
widths of these levels were modified on the basis of the
estimated J values. Neutron and radiation widths of the
negative resonance level were also modified so as to
reproduce the thermal capture cross section according to the
above modification of the neutron widths. Scattering radius
was taken from the graph (Fig. 1, part A) given by
Mughabghab et al.
No modification was performed for JENDL-4.0.
Unresolved resonance region: 8.468 keV - 860 keV
The parameters were obtained by fitting to the total and
capture cross sections calculated from POD /3/. The
unresolved parameters should be used only for self-shielding
calculation.
Thermal cross sections and resonance integrals at 300 K
----------------------------------------------------------
0.0253 eV res. integ. (*)
(barns) (barns)
----------------------------------------------------------
Total 6.3698E+00
Elastic 5.8896E+00
n,gamma 4.8020E-01 8.7525E+00
----------------------------------------------------------
(*) Integrated from 0.5 eV to 10 MeV.
MF= 3 Neutron cross sections
MT= 1 Total cross section
Calculated with POD code /3/.
MT= 2 Elastic scattering cross section
Obtained by subtracting non-elastic cross sections from total
cross sections.
MT= 3 Non-elastic cross section
Sum of partial non-elastic cross sections.
MT= 4,51-91 (n,n') cross section
Calculated with POD code /3/.
MT= 16 (n,2n) cross section
Calculated with POD code /3/.
MT= 17 (n,3n) cross section
Calculated with POD code /3/.
MT= 22 (n,na) cross section
Calculated with POD code /3/.
MT= 28 (n,np) cross section
Calculated with POD code /3/.
MT= 32 (n,nd) cross section
Calculated with POD code /3/.
MT=102 Capture cross section
Calculated with POD code /3/.
MT=103 (n,p) cross section
Calculated with POD code /3/.
MT=104 (n,d) cross section
Calculated with POD code /3/.
MT=105 (n,t) cross section
Calculated with POD code /3/.
MT=106 (n,He3) cross section
Calculated with POD code /3/.
MT=107 (n,a) cross section
Calculated with POD code /3/.
MT=203 (n,xp) cross section
Calculated with POD code /3/.
MT=204 (n,xd) cross section
Calculated with POD code /3/.
MT=205 (n,xt) cross section
Calculated with POD code /3/.
MT=206 (n,xHe3) cross section
Calculated with POD code /3/.
MT=207 (n,xa) cross section
Calculated with POD code /3/.
MF= 4 Angular distributions of emitted neutrons
MT= 2 Elastic scattering
Calculated with POD code /3/.
MF= 6 Energy-angle distributions of emitted particles
MT= 16 (n,2n) reaction
Neutron spectra calculated with POD/3/.
MT= 17 (n,3n) reaction
Neutron spectra calculated with POD/3/.
MT= 22 (n,na) reaction
Neutron spectra calculated with POD/3/.
MT= 28 (n,np) reaction
Neutron spectra calculated with POD/3/.
MT= 32 (n,nd) reaction
Neutron spectra calculated with POD/3/.
MT= 51 (n,n') reaction
Neutron angular distributions calculated with POD/3/.
MT= 52 (n,n') reaction
Neutron angular distributions calculated with POD/3/.
MT= 53 (n,n') reaction
Neutron angular distributions calculated with POD/3/.
MT= 54 (n,n') reaction
Neutron angular distributions calculated with POD/3/.
MT= 55 (n,n') reaction
Neutron angular distributions calculated with POD/3/.
MT= 56 (n,n') reaction
Neutron angular distributions calculated with POD/3/.
MT= 57 (n,n') reaction
Neutron angular distributions calculated with POD/3/.
MT= 58 (n,n') reaction
Neutron angular distributions calculated with POD/3/.
MT= 59 (n,n') reaction
Neutron angular distributions calculated with POD/3/.
MT= 60 (n,n') reaction
Neutron angular distributions calculated with POD/3/.
MT= 61 (n,n') reaction
Neutron angular distributions calculated with POD/3/.
MT= 62 (n,n') reaction
Neutron angular distributions calculated with POD/3/.
MT= 63 (n,n') reaction
Neutron angular distributions calculated with POD/3/.
MT= 64 (n,n') reaction
Neutron angular distributions calculated with POD/3/.
MT= 65 (n,n') reaction
Neutron angular distributions calculated with POD/3/.
MT= 66 (n,n') reaction
Neutron angular distributions calculated with POD/3/.
MT= 67 (n,n') reaction
Neutron angular distributions calculated with POD/3/.
MT= 68 (n,n') reaction
Neutron angular distributions calculated with POD/3/.
MT= 69 (n,n') reaction
Neutron angular distributions calculated with POD/3/.
MT= 70 (n,n') reaction
Neutron angular distributions calculated with POD/3/.
MT= 71 (n,n') reaction
Neutron angular distributions calculated with POD/3/.
MT= 72 (n,n') reaction
Neutron angular distributions calculated with POD/3/.
MT= 73 (n,n') reaction
Neutron angular distributions calculated with POD/3/.
MT= 74 (n,n') reaction
Neutron angular distributions calculated with POD/3/.
MT= 75 (n,n') reaction
Neutron angular distributions calculated with POD/3/.
MT= 76 (n,n') reaction
Neutron angular distributions calculated with POD/3/.
MT= 77 (n,n') reaction
Neutron angular distributions calculated with POD/3/.
MT= 78 (n,n') reaction
Neutron angular distributions calculated with POD/3/.
MT= 79 (n,n') reaction
Neutron angular distributions calculated with POD/3/.
MT= 80 (n,n') reaction
Neutron angular distributions calculated with POD/3/.
MT= 81 (n,n') reaction
Neutron angular distributions calculated with POD/3/.
MT= 82 (n,n') reaction
Neutron angular distributions calculated with POD/3/.
MT= 91 (n,n') reaction
Neutron spectra calculated with POD/3/.
MT= 203 (n,xp) reaction
Proton spectra calculated with POD/3/.
MT= 204 (n,xd) reaction
Deuteron spectra calculated with POD/3/.
MT= 205 (n,xt) reaction
Triton spectra calculated with POD/3/.
MT= 206 (n,xHe3) reaction
He3 spectra calculated with POD/3/.
MT= 207 (n,xa) reaction
Alpha spectra calculated with POD/3/.
MF=12 Gamma-ray multiplicities
MT= 3 Non-elastic gamma emission
Calculated with POD code /3/.
MF=14 Gamma-ray angular distributions
MT= 3 Non-elastic gamma emission
Assumed to be isotropic.
MF=15 Gamma-ray spectra
MT= 3 Non-elastic gamma emission
Calculated with POD code /3/.
***************************************************************
* Nuclear Model Calculations with POD Code /3/ *
***************************************************************
1. Theoretical models
The POD code is based on the spherical optical model, the
distorted-wave Born approximaiton (DWBA), one-component exciton
preequilibrium model, and the Hauser-Feshbach-Moldauer statis-
tical model. With the preequilibrim model, semi-empirical
pickup and knockout process can be taken into account for
composite-particle emission. The gamma-ray emission from the
compound nucleus can be calculated within the framework of the
exciton model. The code is capable of reading in particle
transmission coefficients calculated by separate spherical or
coupled-channel optical model code.
2. Optical model parameters
Neutrons:
Coupled-channel optical model parameters /4/
Protons:
Koning and Delaroche /5/
Deuterons:
Lohr and Haeberli /6/
Tritons:
Becchetti and Greenlees /7/
He-3:
Becchetti and Greenlees /7/
Alphas:
Lemos /8/ potentials modified by Arthur and Young /9/
3. Level scheme of Rb- 85
-------------------------
No. Ex(MeV) J PI
-------------------------
0 0.00000 5/2 -
1 0.15116 3/2 -
2 0.28099 1/2 -
3 0.51401 9/2 +
4 0.73182 3/2 -
5 0.86898 7/2 -
6 0.88582 1/2 -
7 0.91970 3/2 -
8 0.91971 5/2 -
9 0.95095 5/2 +
10 1.17500 9/2 +
11 1.17553 5/2 -
12 1.29337 13/2 +
13 1.29594 3/2 -
14 1.38421 7/2 -
15 1.44506 7/2 -
16 1.44921 5/2 +
17 1.49629 1/2 -
18 1.63146 5/2 -
19 1.66863 1/2 +
20 1.74780 11/2 +
21 1.78693 5/2 +
22 1.79228 1/2 -
23 1.80220 9/2 +
24 1.85262 3/2 +
25 1.89100 5/2 +
26 1.92970 5/2 -
27 1.95003 1/2 -
28 1.99990 1/2 -
29 2.02811 3/2 -
30 2.03950 1/2 -
31 2.05300 7/2 +
32 2.08760 3/2 -
-------------------------
Levels above 2.09760 MeV are assumed to be continuous.
4. Level density parameters
Energy-dependent parameters of Mengoni-Nakajima /10/ were used
----------------------------------------------------------
Nuclei a* Pair Esh T E0 Ematch Elv_max
1/MeV MeV MeV MeV MeV MeV MeV
----------------------------------------------------------
Rb- 86 9.932 0.000 0.007 0.898 -1.348 5.547 1.738
Rb- 85 10.720 1.302 1.529 0.855 -0.855 7.650 2.088
Rb- 84 11.060 0.000 2.125 0.783 -1.914 5.688 0.797
Rb- 83 10.507 1.317 2.990 0.786 -0.643 7.067 2.056
Kr- 85 11.890 1.302 0.718 0.695 0.285 5.433 2.637
Kr- 84 11.089 2.619 1.235 0.745 1.364 7.286 3.951
Kr- 83 11.668 1.317 2.381 0.710 -0.316 6.290 1.889
Br- 83 10.507 1.317 1.382 0.813 -0.276 6.734 2.134
Br- 82 10.599 0.000 2.092 0.832 -2.117 6.154 1.261
Br- 81 10.293 1.333 2.879 0.880 -1.411 8.480 1.587
----------------------------------------------------------
5. Gamma-ray strength functions
M1, E2: Standard Lorentzian (SLO)
E1 : Generalized Lorentzian (GLO) /11/
6. Preequilibrium process
Preequilibrium is on for n, p, d, t, He-3, and alpha.
Preequilibrium capture is on.
References
1) M.Ohkubo et al, J. Nucl. Sci. Technol. 21, 254 (1984).
2) S.F.Mughabghab et al., "Neutron Cross Sections, Vol. I,
Part A", Academic Press (1981).
3) A.Ichihara et al., JAEA-Data/Code 2007-012 (2007).
4) S.Kunieda et al., J. Nucl. Sci. Technol. 44, 838 (2007).
5) A.J.Koning, J.P.Delaroche, Nucl. Phys. A713, 231 (2003).
6) J.M.Lohr, W.Haeberli, Nucl. Phys. A232, 381 (1974).
7) F.D.Becchetti,Jr., G.W.Greenlees, "Polarization
Phenomena in Nuclear Reactions," p.682, The University
of Wisconsin Press (1971).
8) O.F.Lemos, Orsay Report, Series A, No.136 (1972).
9) E.D.Arthur, P.G.Young, LA-8626-MS (1980).
10) A.Mengoni, Y.Nakajima, J. Nucl. Sci. Technol. 31, 151
(1994).
11) J.Kopecky, M.Uhl, Nucl. Sci. Eng. 41, 1941 (1990).