95-Am-241
95-AM-241 JAERI+ EVAL-Mar00 T.Nakagawa, O.Iwamoto, et al.
JAERI-R 2001-059 DIST-MAR02 REV2-MAR01 20010314
----JENDL-3.3 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
***********************************************************
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 Kholkhlov 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 adopted by Maslov et al. which
were mainly taken from 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 repriduced 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 ofpartiacl cross sections)
MT=18 Fission cross section
Based on the experimental data of Hirakawa /15/,
Prindre et al. /16/, Aleksandrov et al. /17/, Cance et al.
/18/, Dabbs et al. /10/, Aleksandrov et al. /19/,
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 is 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) Gayther D.B. and Thomas B.W.: 1977 Kiev, Vol. 3, p.3 (1977).
12) Vanpraet G. et al.: 1985 Santa Fe, Vol.1, p.493 (1985).
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).
16) Prindre A.L., et al.: Phys. Rev., C20, 1824 (1979)
17) Aleksandrov B.M. et al.: Atomnaya Energiya, 46, 416 (1979).
18) Cance M., et al.: CEA-N-2194 (1981).
19) Aleksandrov B.M. et al.: Yadernye Konstanty, 1/50, 3 (1983).
20) Vorotnikov P.E. et al.: Sov. J. Nucl. Phys., 44, 1403 (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, 7 (1997).
24) Wisshak K. et al.: Nucl. Sci. Eng., 81, 396 (1982).
========== COMMENT TO Maslov's Evaluation ========================
95-Am-241 MINSK BYEL EVAL-MAY96
DIST-MAY96
V.M. MASLOV, E.Sh. SUKHOVITSKIJ,
Yu.V. PORODZINSKIJ, A.B. KLEPATSKIJ,
G.B. MOROGOVSKIJ
STATUS
EVALUATION WAS MADE UNDER THE PROJECT AGREEMENT CIS-03-95
WITH INTERNATIONAL SCIENCE AND TECHNOLOGY CENTER (MOSCOW).
FINANCING PARTY OF THE CENTER FOR THE PROJECT IS JAPAN.
EVALUATION WAS REQUESTED BY Y.KIKUCHI (JAERI, TOKAI)
MF=1 GENERAL INFORMATION
MT=451 COMMENTS AND DICTIONARY
MT=452 TOTAL NUMBER OF NEUTRONS PER FISSION
SUM OF MT=455 AND MT=456.
MT=455 DELAYED NEUTRON DATA
NUMBER OF DELAYED NEUTRONS AND
DECAY CONSTANTS FROM BRADY ET AL./1 /
MT=456 NUMBER OF PROMPT NEUTRONS PER FISSION
MADLAND-NIX MODEL CALCULATIONS /2/ FITTED TO
THE EXPERIMENTAL ENERGY DEPENDENCE 3.078+0.146En
OF KHOKHLOV ET AL. /3/ BELOW 5.5 MEV. ABOVE
EMISSIVE FISSION THRESHOLD A SUPERPOSITION OF
NEUTRON EMISSION IN (N,XNF) REACTIONS /4/ AND PROMPT
FISSION NEUTRONS IS EMPLOYED.
MF=2 RESONANCE PARAMETERS
MT=151 RESONANCE PARAMETERS (MLBW)
RESOLVED RESONANCE REGION : 1.0E-5 - 150 EV
PARAMETERS FOR BREIT -WIGNER FORMULA ARE BASED ON
THE DATA OF ADAMCHUK ET AL. /5/, DERRIEN AND LUCAS /6/,
BOWMAN ET AL. /7/, GERASIMOV /8/, DABBS ET AL. /9/,
WESTON AND TODD /10/ AND VANPRAET ET AL. /11/.
UNRESOLVED RESONANCE REGION : 0.15 - 41.3483 KEV.
ENERGY INDEPENDENT PARAMETERS:
R=9.157 FM FROM OPTICAL MODEL CALCULATIONS
S1=2.204E-4 FROM OPTICAL MODEL CALCULATIONS
S2=1.022E-4 FROM OPTICAL MODEL CALCULATIONS
ENERGY DEPENDENT PARAMETERS:
S0 - DECREASES FROM .864-4 (0.15KEV)TO .807-4 (41.4keV)
D - SPIN DEPENDENT, NORMALIZED TO =0.505 EV
WITH ACCOUNT OF LEVEL MISSING /12/
WF -SPIN DEPENDENT AS DEFINED BY THE TRANSITION STATE
SPECTRA AT INNER AND OUTER BARRIER HUMPS,NORMALIZED
TO =0.38 mEV TO FIT UNRESOLVED RESONANCE REGION
EXPERIMENTAL FISSION DATA /9/.
WG - FROM CASCADE MODEL WITH ACCOUNT OF FISSION
COMPETITION,SPIN DEPENDENT. NORMALIZED TO =
0.0484 EV.
CALCULATED 2200 M/S CROSS SECTIONS AND RESONANCE
INTEGRALS.
2200 M/SEC RES.INTEG.
TOTAL 599.469 b -
ELASTIC 11.531 b -
FISSION 3.136 b 14.508
CAPTURE 584.802 b 1351.200
MF=3 NEUTRON CROSS SECTIONS
MT=1,4,51-60,91,102. TOTAL, ELASTIC AND INELASTIC
SCATTERING, CAPTURE CROSS SECTION
TOTAL,DIRECT ELASTIC AND DIRECT INELASTIC FOR MT=51,
52,53 AND OPTICAL TRANSMISSION COEFFICIENTS FROM
COUPLED CHANNELS CALCULATIONS.
THE DEFORMED OPTICAL POTENTIAL USED:
VR=46.15-0.3*E(MEV) RR=1.26 FM AR=0.615 FM
WD= 3.56+0.4*E(MEV) E < 10 MEV RD=1.24 FM
WD= 7.77 E => 10 MEV AD=0.5 FM
VSO=6.2 RSO=1.12 ASO=0.47 B2=0.181 B4=0.076
FOUR LOWER LEVELS OF GROUND STATE ROTATIONAL BAND
ARE COUPLED.
CAPTURE,COMPOUND ELASTIC AND INELASTIC BY STATISTICAL
MODEL, SEE MT=18-21
ABOVE NEUTRON ENERGY 5 MEV CAPTURE IS ASUMED TO BE
0.001 BARN AS PREDICTED BY DIRECT AND SEMI-DIRECT
CAPTURE CALCULATIONS
ADOPTED LEVEL SCHEME OF AM-241 FROM NUCLEAR DATA
SHEETS /13/ (9 LEVELS) PLUS 1 LEVEL ADDED FOR BAND
K,P=5/2+ ACCORDING TO EJ=A(J(J+1)-K(K+1))
No ENERGY(MEV) SPIN-PARITY K
g.s. 0.0 5/2 - 5/2
1 0.041176 7/2 - 5/2
2 0.09365 9/2 - 5/2
3 0.158 11/2 - 5/2
4 0.20588 5/2 + 5/2
5 0.234 13/2 - 5/2 *
6 0.235 7/2 + 5/2
7 0.239 3/2 - 3/2
8 0.272 9/2 + 5/2
9 0.273 5/2 - 3/2
10 0.312 15/2 - 5/2
* - ADDED
OVERLAPPING LEVELS ARE ASSUMED ABOVE 0.312 MEV
LEVEL DENSITY PARAMETERS: SEE MT 18-21
MT=16,17. (N,2N) AND (N,3N) CROSS SECTION
FROM STATISTICAL MODEL CALCULATIONS /14/ WITH THE
ACCOUNT OF PRE-EQUILIBRIUM NEUTRON EMISSION:SEE MT=18-21
MT=18,19,20,21. FISSION CROSS SECTION IS CALCULATED WITHIN
STATISTICAL MODEL /15/, THE MEASURED DATA OF:
DABBS ET AL./9/, HAGE ET AL./16/, WISSHAK ET AL./17/,
KUPRIYANOV ET AL./18/, KNITTER ET AL. /19/,
PRINDLE ET AL./20/, FOMUSHKIN ET AL./21/ ARE FITTED.
THE FIRST CHANCE FISSION MT=19 IS CALCULATED WITH
THE CONTRIBUTION OF EMISSIVE FISSION TO TOTAL FISSION
CROSS SECTION IS CALCULATED ACCORDING TO /14,15/.
MF=4 ANGULAR DISTRIBUTIONS OF SECONDARY NEUTRONS
FOR MT=2,51,52,53 FROM COUPLED CHANNELS CALCULATIONS
WITH ADDED ISOTROPIC STATISTICAL CONTRIBUTION.
MT=16,17,18,52,54-60,91,16 ISOTROPIC
MF=5 ENERGY DISTRIBUTIONS OF SECONDARY NEUTRONS
ENERGY DISTRIBUTIONS FOR MT=16,17 WERE
CALCULATED BY STATISTICAL MODEL OF CASCADE NEUTRON
EMISSION TAKING INTO ACCOUNT THE HISTORY OF THE DECAY
WITH THE ALLOWANCE OF PRE-EQUILLIBRIUM EMISSION OF
THE FIRST NEUTRON /4/
ENERGY DISTRIBUTIONS FOR MT=18,19,20,21 WERE
CALCULATED BY MADLAND-NIX MODEL /2/ WITH ACCOUNT FOR
THE EFFECTS OF AND COMPETITION BETWEEN MULTIPLE-CHANCE
FISSION PROCESSES UP THROUGH THIRD-CHANCE FISSION
WITH THE ALLOWANCE OF PRE-EQUILLIBRIUM EMISSION OF
THE FIRST NEUTRON /4/
REFERENCES
1. Brady M.C., Wright R.Q., England T.R., Report ORNL/CSD/TM-
226(1991), IAEA-NDS-102, 1992.
2. Madland D.G., Nix J.R., Nucl. Sci. Eng., 81, 213, (1982).
3. Khokhlov Yu.A., Ivanin I.A., In'kov V.I., et al., Proc of
Int. Conf. on Nucl. Data for Sci. and Tech., 9-13 May,
Gatlinburg, v.1, p.272, 1994.
4. Maslov V.M., Porodzinskij Yu.V.,Sukhovitskij E.Sh., Proc.
Int. Conf. on Neutron Physics, 14-18 Sept., Kiev, USSR,
v.1, p.413, 1988.
5. Adamchuk Ju.V. et al., Nucl. Sci. Eng., 61, 356 (1976).
6. Derrien H., Lucas B., 75 WASH., 2, 637 (1975).
7. Bowman C.D. et al., Phys. Rev. B, 137,326 (1965).
8. Gerasimov V.F., Yadernaja Fizica, 4, (5), 985 (1966).
9. Dabbs J.W.T. et al., Nucl. Sci. Eng., 83, 22, (1983).
10. Weston L.W., Todd J.H., Nucl. Sci. Eng., 61, 356, (1976).
11. Vanpraet G. et al., Proc. Int. Conf. on Nuclear Data for Basic
and Applied Sci., Santa Fe, USA, (1985), vol. 1, 493.
12. Porodzinskij Yu.V.,Sukhovitskij E.Sh., Nuclear Constants,
4, 27,1987.
13. ENDSF, 1995
14. Ignatjuk A.V., Maslov V.M., Pashchenko A.B. Sov. J. Nucl.
Phys. 47, 224 (1988).
15. Maslov V.M. et al. INDC(BLR)-003, 1996
16. Hage W. et al. Nucl. Sci. Eng., 78, 248 (1981).
17. Wisshak K. et al. Nucl. Sci. Eng., 76, 148 (1980).
18. Kupriyanov S. et al. Sov. J. At. Energy, 45, 176, 1979
19. Knitter et al. Atomkernenergie, Kerntechnik,3,205, 1979
20. Prindle et al., Phys.Rev. C20, 1824, 1979
21. Fomushkin E.F.et al. Sov. J. Nucl. Phys.5, 689, 1967