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93-Np-236 JAERI EVAL-MAR93 T.NAKAGAWA
DIST-JAN09 20090105
----JEFF-311 MATERIAL 9343
-----INCIDENT NEUTRON DATA
------ENDF-6 FORMAT
*************************** JEFF-3.1.1 *************************
** **
** Original data taken from: JEFF-3.1 **
** **
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***************************** JEFF-3.1 *************************
** **
** Original data taken from: JENDL-3.3 **
** **
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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
93-03 NEW EVALUATION WAS MADE FOR JENDL-3.2.
MF=1 GENERAL INFORMATION
MT=451 DESCRIPTIVE DATA AND DICTIONARY
MT=452 TOTAL NUMBER OF NEUTRONS PER FISSION
SUM OF NU-P (MT=456) AND NU-D (MT=455).
MT=455 DELAYED NEUTRON DATA
DETERMINED FROM SYSTEMATICS BY TUTTLE/1/, BENEDETTI/2/ AND
WALDO ET AL./3/ DECAY CONSTANTS WERE TAKEN FROM THE EVALU-
ATION FOR NP-238 BY BRADY AND ENGLAND/4/.
MT=456 NUMBER OF PROMPT NEUTRONS
BASED ON THE DATA BY LINDNER AND SEEGMILLER /5/ AND
HOWERTON'S SYSTEMATICS/6/.
MF=2 RESONANCE PARAMETERS
MT=151 NO RESONANCE PARAMETERS ARE GIVEN.
THERMAL CROSS SECTIONS AND CALCULATED RES. INTEGRAL (BARNS)
0.0253 EV RESONANCE INTEGRAL
TOTAL 3483. -
ELASTIC 12.27 -
FISSION 2770. 1030
CAPTURE 701. 259
MF=3 NEUTRON CROSS SECTIONS
BELOW 20 KEV
============
MT= 1 TOTAL CROSS SECTION
SUM OF PARTIAL CROSS SECTIONS.
MT= 2 ELASTIC SCATTERING CROSS SECTION
CALCULATED WITH OPTICAL MODEL CODE CASTHY/7/.
MT= 18 FISSION CROSS SECTION
BASED ON THE DATA MEASURED BY VAL'SKIY ET AL./8/
MT= 102 CAPTURE CROSS SECTION
CAPTURE-TO-FISSION RATIO WAS ASSUMED TO BE 0.253 THAT WAS
OBTAINED FROM THE CAPTURE CROSS SECTION CALCULATED AT 20 KEV
AND THE FISSION CROSS SECTION.
ABOVE 20 KEV
============
MT= 1 TOTAL CROSS SECTION
CALCULATED WITH OPTICAL MODEL CODE CASTHY/7/. PARAMETERS
ARE LISTED IN TABLE 1.
MT= 2 ELASTIC SCATTERING CROSS SECTION
TOTAL - (SUM OF PARTIAL CROSS SECTIONS)
MT= 16, 17 (N,2N) AND (N,3N) CROSS SECTIONS
CALCULATED FROM A FORMULA GIVEN BY SAGEV AND CANER/9/.
THE REACTION CROSS SECTIONS CALCULATED WITH CASTHY WAS
ADOPTED AS THE NON-ELASTIC SCATTERING CROSS SECTION.
MT= 18 FISSION CROSS SECTION
ABOVE 5 MEV, A SIMPLE FORMULA BY BYCHKOV ET AL./9/ WAS USED.
EXPERIMENTAL DATA OF BRITT AND WILHELMY/10/ AND SYSTEMA-
TICS/11/ WERE CONSIDERED. THE CROSS-SECTION CURVE WAS
SMOOTHLY CONNECTED AT 20 KEV TO THE DATA OF VAL'SKIY ET
AL./8/
MT= 4, 51-54, 91 INELASTIC SCATTERING CROSS SECTION
CALCULATED WITH CASTHY (OPTICAL AND STATISTICAL MODEL).
PARAMETERS USED ARE LISTED IN TABLES 1, 2 AND 3. THE LEVEL
SCHEME WAS TAKEN FROM EVALUATION BY SCHMORAK/12,13/.
MT= 102 CAPTURE CROSS SECTION
CALCULATED WITH CASTHY. AVERAGE CAPTURE WIDTH AND LEVEL
SPACING WAS ASSUMED TO BE 0.035 EV AND 0.11EV, RESPECTIVELY.
DIRECT AND SEMI-DIRECT CAPTURE WAS CALCULATED FROM A SIMPLE
FORMULA OF BENZI AND REFFO/14/.
MT= 251 MU-L
CALCULATED WITH CASTHY
MF=4 ANGULAR DISTRIBUTIONS OF SECONDARY NEUTRONS
MT= 2, 51-54, 91
CALCULATED WITH CASTHY
MT=16, 17, 18
ASSUMED TO BE ISOTROPIC IN THE LABORATORY SYSTEM.
MF=5 ENERGY DISTRIBUTIONS OF SECONDARY NEUTRONS
MT=16, 17, 91
EVAPORATION SPECTRA OBTAINED FROM THE LEVEL DENSITY
PARAMETERS WERE GIVEN.
MT=18
EVAPORATION SPECTRA. TEMPERATURE WAS DETERMINED FROM
SYSTEMATICS BY SMITH ET AL./15/
TABLE 1 OPTICAL POTENTIAL PARAMETERS
DETERMINED BY MURATA/16/ EXCEPT A CONSTANT TERM OF V
THAT WAS SELECTED SO AS TO REPRODUCE S0 OF 1.0E-4.
-------------------------------------------------------------
V = 40.5 - 0.05*E (MEV)
WS = 6.5 + 0.15*E (MEV): DERRIVATIVE WOOD-SAXON TYPE
VSO = 7.0 (MEV)
R0 = RSO = 1.32, RS = 1.38 (FM)
A = B = ASO = 0.47 (FM)
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TABLE 2 LEVEL SCHEME OF NP-236 /12,13/
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NO. ENERGY(MEV) SPIN-PARITY
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G.S 0.0 6 -
1 0.060 1 +
2 0.231 3 -
3 0.273 4 -
4 0.324 5 -
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LEVELS ABOVE 0.370 MEV WERE ASSUMED TO BE OVERLAPPING.
TABLE 3 LEVEL DENSITY PARAMETERS FOR GILBERT AND CAMERON
FORMULA, BASED ON THE EXCITED LEVELS GIVEN IN ENSDF.
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PAIRING SPIN-CUTOFF F.
A(1/MEV) T(MEV) ENERGY(MEV) (MEV**0.5) EX(MEV)
-------------------------------------------------------------
NP-234* 27.16 0.0 17.57 3.1410
NP-235 31.4 0.35 0.57 31.16 3.2900
NP-236 28.0 0.35 0.0 29.50 2.2579
NP-237 29.6 0.39 0.49 30.42 3.7161
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* TAKEN FROM GILBERT AND CAMERON/17/
REFERENCES
1) R.J.TUTTLE: INDC(NDS)-107/G+SPECIAL, P.29 (1979).
2) G.BENEDETTI, ET AL.: NUCL. SCI. ENG., 80, 379 (1982).
3) R.WALDO ET AL.: PHYS. REV., C23, 1113 (1981).
4) M.C.BRADY AND T.R.ENGLAND: NUCL. SCI. ENG., 103, 129 (1989).
5) M.LINDNER AND D.W.SEEGMILLER: RADIOCHIMICA ACTA, 49, 1(1990).
6) R.J.HOWERTON: NUCL. SCI. ENG., 62, 438 (1977).
7) S.IGARASI AND T.FUKAHORI: JAERI 1321 (1991).
8) G.V.VAL'SKIY ET AL.: PROC. 1ST INT. CONF. ON NEUTRON PHYSICS,
KIEV 1987, VOL. 3, P.99 (1987). DATA WERE TAKEN FROM EXFOR
40995
9) V.M.BYCHKOV ET AL.: INDC(CCP)-184/L (1982).
10) H.C.BRITT AND J.B.WILHELMY: NUCL. SCI. ENG., 72, 222 (1979).
11) J.W.BEHRENS AND R.J.HOWERTON: NUCL. SCI. ENG., 65, 464 (1978).
12) M.R.SCHMORAK: NUCLEAR DATA SHEETS, 63, 139 (1991).
13) ENSDF: EVALUATED NUCLEAR STRUCTURE DATA FILE, BNL/NNDC, AS OF
JAN. 1993.
14) V.BENZI AND G.REFFO: CCDN-NW/10 (1969).
15) A.B.SMITH ET AL.: ANL/NDM-50 (1979).
16) H.MATSUNOBU ET AL.: PROC. IN. CONF. ON NUCLEAR CROSS SECTIONS
FOR TECHNOL., KNOXVILLE, 1979, P.715 (1980).
17) A.GILBERT AND A.G.W.CAMERON: CAN. J. PHYS., 43, 1446 (1965).
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