Short Comment to Iron Data in JENDL-3.3
Chikara Konno1, Kentaro Ochiai1, Masayuki Wada2 and Satoshi Sato1
1Fusion Research and Development Directorate, Japan Atomic Energy Agency
2Japan Computer System

We presented analysis results of the iron integral experiment at JAEA FNS withrecent nuclear data libraries (JENDL-3.3, FENDL-2.1, JEFF-3.1 and ENDF/B-VII.0) andMCNP-4C at the last symposium on nuclear data. The calculation with JENDL-3.3
overestimated measured neutrons below ~ 10 keV for the iron experiment, while othercalculations agreed with the measurements well. Thus we investigate what of the iron data inJENDL-3.3 causes the overestimation based on ENDF/B-VII.0.
The Sn code DORT was used for this analysis because this code gives almost thesame results as MCNP quickly. Multigroup libraries with self-shielding correction wereproduced with the TRANSX code from MATXS files. The MATXS files supplied fromJAEA Nuclear Data Center were adopted for JENDL-3.3. Since MATXS files forENDF/B-VII.0 were not released officially, they were produced with the NJOY99.161 codeand patch from BNL National Nuclear Data center for ourselves.
In order to examine which iron isotopes caused the overestimation, we calculated
neutron spectra of the iron experiment with DORT, where iron isotopes in JENDL-3.3 werereplaced with those in ENDF/B-VII.0 one by one. As a result, it was found out that the Fe-57
data in JENDL-3.3 caused the overestimation of measured neutrons below ~ 10 keV in theiron experiment. The elastic and first inelastic scattering cross section data of Fe-57 inJENDL-3.3 was different from that in ENDF/B-VII.0 largely. It was confirmed that the firstinelastic scattering cross section of Fe-57 in JENDL-3.3 caused the overestimation of theiron experiment through the DORT calculations where the elastic and first inelastic
scattering cross section data of Fe-57 in JENDL-3.3 were replaced with those in
ENDF/B-VII.0 separately. The Fe-57 data should be revised in JENDL-4.

Short Comment to Iron Data in JENDL-3.3
Japan Atomic Energy Agency
Japan Computer System

Chikara Konno, Kentaro Ochiai, Satoshi Sato
Masayuki WadaBackground We presented analysis results of the iron integral experiment at JAEA FNS
with recent nuclear data libraries and MCNP-4C at the last symposium.
- Calculation with JENDL-3.3 overestimated measured neutrons below ~10 keV for the iron experiment, while other calculations agreed well.
1.5(unit : mm)

200

NE213
PRC
BF3
ENDF/B-VII.0
JEFF-3.1
FENDL-2.1
JENDL-3.3

10-5

101.2
1.1
1.0

Iron Experiment
Neutron Spectra
at depth of 310 mm
10-6Experimental configuration

10-5

ENDF/B-VII.0
JEFF-3.1
FENDL-2.1
JENDL-3.3

1.3-610-7

950

Iron Experiment
Neutron flux
0.1 < En < 1 keV

1.4

Calc. / Expt.

1000 φD-T
NeutronSource

Neutron Flux [n/cm2/lethargy/source]

Iron (Test region)

10-4

10-3

0.9
0.8
10-2

10-1

100

101

Expt. Error

0200
400
600
800
Depth in the assembly [mm]Neutron Energy [MeV]

1000Objective
 To investigate what of the iron data in JENDL-3.3 caused the overestimation
based on ENDF/B-VII.0.

Method Code : Sn Code DORT (which gives almost the same results as MCNP quickly) Multigroup libraries with self-shielding correction were produced withTRANSX code from MATXS files of JENDL-3.3 (from JAEA Nuclear DataCenter) and ENDF/B-VII.0 (processed with NJOY99.161).

10-6
ENDF/B-VII.0
JENDL-3.3
Fe-54: ENDF/B-VII.0, others:JENDL-3.3
Fe-56:ENDF/B-VII.0, others:JENDL-3.3
Fe-57:ENDF/B-VII.0, others:JENDL-3.3
Fe-58:ENDF/B-VII.0, others: JENDL-3.3

10-7
10-6

10-5

10-4

10-3

10-2

10-1

ENDF/B-VII.0
JENDL-3.3

101

10-1

10101

10-6

15

10-5

10-4

1.2
1.1
1.00.9
0.8

10-3

10-2

10-1

100

200
400
600
800
Depth in the assembly [mm]5Fe-57 in JENDL-3.3 causes
the overestimation!

01010-1

1010-2

10-1

100

101

010

1

Neutron Energy [MeV]MT2 and MT51 of fe-57 arelargely different between
JENDL-3.3 and ENDF/B-VII.0.

ENDF/B-VII (B7)
JENDL-3.3 (J33)J33 (elastic scatteringof Fe-57 is B7)
J33 (first inelastic scatteringof Fe-57 is B7)

1.3
1.2
1.1
1.0

0.8-2

10-3

Iron Experiment
Neutron flux
0.1 < En < 1 keV

1.4ENDF/B-VII.0
JENDL-3.3

0.9
1000

10-4

1.5

The first inelastic scattering cross sectionof Fe-57

1010-5

Neutron Energy [MeV]Expt. Error

010-6

101

Calc. / Expt.

Calc. / Expt.

Cross section [b]ENDF/B-VII (B7)
JENDL-3.3 (J33)
Fe-54:B7,others:J33
Fe-56:B7,others:J33
Fe-57:B7,others:J33
Fe-58:B7,others:J33

1.3

ENDF/B-VII.0 (B7)
JENDL-3.3
JENDL-3.3 (elastic scattering of Fe-57 is B7)
JENDL-3.3 (first inelastic scattering cross section of Fe-57 is B7)

10-7

Neutron Energy [MeV]

1.5
Iron Experiment
Neutron flux
0.1 < En < 1 keV

10-6-3

Neutron Energy [MeV]

1.4

10-52100

10-2100

Iron Experiment
Neutron Spectra
at depth of 310 mm

Elastic cross section of Fe-57

102

Neutron Flux [n/cm /lethargy/source]-5210103Iron Experiment
Neutron Spectra
at depth of 310 mm

Cross section [b]Neutron Flux [n/cm /lethargy/source]

Results and Discussion

Expt. Error

0200
400
600
800
Depth in the assembly [mm]1000

MT51 of fe-57 in JENDL-3.3
causes the overestimation!!

Conclusion The first inelastic scattering cross section data of Fe-57 in JENDL-3.3
caused the overestimation of measured neutrons below ~ 10 keV in the ironintegral experiment at JAEA/FNS.
 Fe-57 data should be revised in JENDL-4.