95-Am-241
95-AM-241 JAERI+ EVAL-Mar00 T.Nakagawa, O.Iwamoto, et al.
JAERI-R 2001-059 DIST-Dec03 REV3-Dec03 20031217
----JENDL-3.3u MATERIAL 9543
-----INCIDENT NEUTRON DATA
------ENDF-6 FORMAT
History
82-03 EVALUATION FOR JENDL-2 WAS MADE BY Y.KIKUCHI (JAERI) /1/.
88-03 RE-EVALUATION FOR JENDL-3 WAS MADE BY T.NAKAGAWA (JAERI)
/2/
01-03 JENDL-3.3.
New evaluation made by Maslov et al. /3/ was adopted and
modified by by T.Nakagawa (NDC/JAERI)
***** Modified parts from JENDL-3.2 ********************
All data
***********************************************************
03-12 (MF4,MT18) added. (MF5,MT18) modified.
MF=1 General Information
MT=451 Descriptive data and directory records
MT=452 Number of neutrons per fission
Sum of MT's= 455 and 456
MT=455 Delayed neutron data
Nu-d was based on the experimental data of Saleh et al./4/,
and the semi-empirical formula of Tuttle /5/ above 8 MeV .
Decay constants were adopted from Saleh et al./4/ and Brady
and England /6/.
MT=456 Number of prompt neutrons per fission
Taken from measurements Khokhlov et al./7/.
MF=2 Resonance Parameters
MT=151 Resolved and unresolved resonance parameters
1) Resolved resonance parameters for MLBW formula (below 150 eV)
The resonance parameters of Maslov et al. which were mainly
based on the data of Derrien and Lucas /8/, were slightly
modified to reproduce well the Yamamoto et al./9/
The parameters of low energy levels were adjusted to the
thermal cross sections and resonance integrals.
2) Unresolved resonance parameters (150 eV - 40 keV)
Average fission cross section to be reproduced was
determined from experimental data of Yamamoto et al./9/
and Dabbs et al./10/, and the capture cross section from
Vanpraet et al./11/ and Gayther et al./12/
The average resonance parameters were determined with ASREP
/13/ to reproduce those average cross sections.
Thermal cross sections and resonance integrals
-------------------------------------------------------
0.0253 eV reson. integ.
-------------------------------------------------------
total 654.44
elastic 11.83
fission 3.14 14.8
capture 639.47 1460
-------------------------------------------------------
MF=3 Neutron Cross Sections
Except for the following reactions, the evaluated data of Maslov
et al. /3/ were adopted.
MT= 1 Total cross section
Data of JENDL-3.2 were adopted. They were calculated with
spherical optical model parameters determined to reproduce
the total cross section measured by Phillips and Howe /14/
V = 43.4 - 0.107*EN (MeV)
Ws= 6.95 - 0.339*EN + 0.0531*EN**2 (MeV)
Wv= 0 , Vso = 7.0 (MeV)
r = rso = 1.282 , rs = 1.29 (fm)
a = aso = 0.60 , b = 0.5 (fm)
MT= 2 Elastic scattering cross section
Calculated as (total - sum of partiacl cross sections)
MT=18 Fission cross section
Based on the experimental data of Hirakawa /15/,
Prindre et al. /16/, Aleksandrov et al. /17,18/, Cance
et al. /19/, Dabbs et al. /10/, Vorotnikov et al./20/,
Wisshak anf Kaeppeler /21/.
MT=102 Capture cross section
Based on the evaluated data of Maslov et al. In the MeV
region, the cross section of direct and semi-direct process
was calculated with DSD code /22/.
MF=4 Angular Distributions of Secondary Neutrons
All data were taken from the evaluation by Maslov et al. /3/
MF=5 Energy Distributions of Secondary Neutrons
All data were taken from the evaluation by Maslov et al. /3/
MF=8 Radiactive Decay Data
MT=102
Decay data were taken from ENSDF.
MF=9 Multiplicities for Production of Radioactive Elements
MT=102
En = 1e-5 - 0.9 eV:
Based on the experimental data of Shinohara et al. /23/
and Wisshak et al./24/
En > 0.9 eV:
Calculation based on Hauser-Feshbach statistical model and
normalized to the experimental data /24/ at 29 keV within
the experimental error. For the calculation, optical
potential was taken from Maslov et al./3/, level scheme
from Wisshak et al./24/
References
1) Kikuchi Y.: JAERI-M 82-096 (1982).
2) Nakagawa T.: JAERI-M 88-008 (1989).
3) Malov V.M. et al.: INDC(BLR)-5 (1996).
4) Saleh H.H. et al.: Nucl. Sci. Eng., 125, 51 (1997).
5) Tuttle R.J.: INDC(NDS)-107/G+Special, p.29 (1979).
6) Brady M.C. and England T.R.: Nucl. Sci. Eng., 103, 129 (1989).
7) Khokhlov Yu.A. et al.: 1994 Gatlinburg, Vol.1, p.272 (1994).
8) Derrien H. and Lucas B.: 1975 Washington, Vol.II, p.637
(1975).
9) Yamamoto S. et al.: Nucl. Sci. Eng., 126, 201 (1997).
10) Dabbs J.W.T. et al.: Nucl. Sci. Eng., 83, 22 (1983).
11) Vanpraet G. et al.: 1985 Santa Fe, Vol.1, p.493 (1985).
12) Gayther D.B. and Thomas B.W.: 1977 Kiev, Vol. 3, p.3 (1977).
13) Kikuchi Y. et al.: JAERI-Data/Code 99-025 (1999).
14) Phillips T.W. and Howe R.E.: Nucl. Sci. Eng., 69, 375(1979).
15) Hirakawa N.: JNC TJ9400 99-007 (1999). [in Japanese]
16) Prindre A.L., et al.: Phys. Rev., C20, 1824 (1979)
17) Aleksandrov B.M. et al.: Sov. At. Energy, 46, 475 (1979).
18) Aleksandrov B.M. et al.: Yadernye Konstanty, 1/50, 3 (1983).
19) Cance M., et al.: CEA-N-2194 (1981).
20) Vorotnikov P.E. et al.: Sov. J. Nucl. Phys., 44, 912 (1986).
21) Wisshak K. and Kaeppeler F.: Nucl. Sci. Eng., 76, 148 (1980).
22) Kawano T.: private communication (1999).
23) Shinohara N. et al.: J. Nucl. Sci. Technol., 34, 613 (1997).
24) Wisshak K. et al.: Nucl. Sci. Eng., 81, 396 (1982).