Forschungszentrum Karlsruhe EFF-DOC-897in der Helmholtz-Gemeinschaft

Re-analysis of TUD Benchmark Experiment on Tungsten Using

JENDL-3.3 Data

U. Fischer a), D. Leichtle a) and R. Perel b)

a)Forschungszentrum Karlsruhe, Germanyb)Hebrew University of Jerusalem, Israel

EFF/EAF Monitoring Meeting, OECD/IEA Headquarters, Paris, May 10-12, 2004

EFF-DOC-897, EFF/EAF Monitoring Meeting, OECD/IEA Headquarters, Paris, May 10-12, 2004 2

Outline

• TUD Experiment on W at FNG– Measurement of neutron & photon flux spectra in W assembly using a

NE 213 liquid-scintillation spectrometer (K. Seidel et al., EFF-DOC-857)– Spectra measured in four positions in W assembly

• Previous analyses (U. Fischer et al, EFF-DOC-860)– MCNP4C calculations for 3D model of W assembly & rack,

spectrometer, neutron generator and experimental hall (FNG)– W data: EFF-2.4 (=JENDL-3.0), FENDL-1(=ENDF/B-VI.0),

FENDL-2(=JENDL-FF)– Comparison of flux spectra & C/E-data– Cross-section data checks

⇒ Re-analysis using recent JENDL-3.3 data⇒ Support for ongoing EFF evaluation of W

(P. Pereslavtsev et al, EFF-DOC 898)

EFF-DOC-897, EFF/EAF Monitoring Meeting, OECD/IEA Headquarters, Paris, May 10-12, 2004 3

W assembly model

spectrometer

P1 P2 P3 P4

5 cm

15 c

m

20 c

m

35 c

m

49 cm

neutron source tungsten

EFF-DOC-897, EFF/EAF Monitoring Meeting, OECD/IEA Headquarters, Paris, May 10-12, 2004 4

Neutron flux spectra in W assembly at P1

100 10110-6

10-5

10-4

10-3

P1 (5 cm)

TUD measurement EFF 2.4 FENDL-2 FENDL-1 JENDL-3.3

Neu

tron

flux

[cm

-2M

eV-1sn

-1]

Neutron energy [MeV]

EFF-DOC-897, EFF/EAF Monitoring Meeting, OECD/IEA Headquarters, Paris, May 10-12, 2004 5

Neutron flux spectra in W assembly at P2

100 10110-7

10-6

10-5

10-4

P2 (15 cm)

TUD measurement EFF 2.4 FENDL-2 FENDL-1

Neu

tron

flux

[cm

-2M

eV-1sn

-1]

Neutron energy [MeV]

EFF-DOC-897, EFF/EAF Monitoring Meeting, OECD/IEA Headquarters, Paris, May 10-12, 2004 6

Neutron flux spectra in W assembly at P3

100 101

10-7

10-6

10-5

P3 (25 cm)

TUD measurement EFF 2.4 FENDL-2 FENDL-1 JENDL-3.3

Neu

tron

flux

[cm

-2M

eV-1sn

-1]

Neutron energy [MeV]

EFF-DOC-897, EFF/EAF Monitoring Meeting, OECD/IEA Headquarters, Paris, May 10-12, 2004 7

100 101

10-8

10-7

10-6

P4 (35 cm)

TUD measurement EFF 2.4 FENDL-2 FENDL-1 JENDL-3.3

Neu

tron

flux

[cm

-2M

eV-1sn

-1]

Neutron energy [MeV]

Neutron flux spectra in W assembly at P4

EFF-DOC-897, EFF/EAF Monitoring Meeting, OECD/IEA Headquarters, Paris, May 10-12, 2004 8

C/E comparison of neutron flux integrals

5 10 15 20 25 30 350,70

0,75

0,80

0,85

0,90

0,95

1,00

1,05

1,10 Neutron flux E>12.5 MeV EFF2 FENDL1 FENDL2 JENDL-3.3

C/E

Detector position [cm]

EFF-DOC-897, EFF/EAF Monitoring Meeting, OECD/IEA Headquarters, Paris, May 10-12, 2004 9

C/E comparison of neutron flux integrals

5 10 15 20 25 30 35

0,4

0,6

0,8

1,0

1,2 Neutron flux 10-12.5 MeV EFF2 FENDL1 FENDL2 JENDL-3.3

C/E

Detector position [cm]

EFF-DOC-897, EFF/EAF Monitoring Meeting, OECD/IEA Headquarters, Paris, May 10-12, 2004 10

C/E comparison of neutron flux integrals

5 10 15 20 25 30 35

0,8

1,0

1,2

1,4

Neutron flux 7.5-10 MeV EFF2 FENDL1 FENDL2 JENDL-3.3

C/E

Detector position [cm]

EFF-DOC-897, EFF/EAF Monitoring Meeting, OECD/IEA Headquarters, Paris, May 10-12, 2004 11

C/E comparison of neutron flux integrals

5 10 15 20 25 30 35

0,8

1,0

1,2

1,4Neutron flux 5-7.5 MeV EFF2

FENDL1 FENDL2 JENDL-3.3

C/E

Detector position [cm]

EFF-DOC-897, EFF/EAF Monitoring Meeting, OECD/IEA Headquarters, Paris, May 10-12, 2004 12

C/E comparison of neutron flux integrals

5 10 15 20 25 30 350,4

0,6

0,8

1,0

1,2

1,4

Neutron flux 2.5-5 MeV EFF2 FENDL1 FENDL2 JENDL-3.3

C/E

Detector position [cm]

EFF-DOC-897, EFF/EAF Monitoring Meeting, OECD/IEA Headquarters, Paris, May 10-12, 2004 13

C/E comparison of neutron flux integrals

5 10 15 20 25 30 350,6

0,8

1,0

1,2Neutron flux 1-2.5 MeV EFF2

FENDL1 FENDL2 JENDL-3.3

C/E

Detector position [cm]

EFF-DOC-897, EFF/EAF Monitoring Meeting, OECD/IEA Headquarters, Paris, May 10-12, 2004 14

C/E comparison of neutron flux integrals

5 10 15 20 25 30 350,70

0,75

0,80

0,85

0,90

0,95

1,00

1,05

1,10

Neutron flux E>1.0 MeV EFF2 FENDL1 FENDL2 JENDL-3.3

C/E

Detector position [cm]

EFF-DOC-897, EFF/EAF Monitoring Meeting, OECD/IEA Headquarters, Paris, May 10-12, 2004 15

natW neutron emission cross-section

0 5 10

0,01

0,1

1

10

natW Ein=14.1 MeV EFF-2.4 FENDL-1 FENDL-2 FZK184 JENDL-3.3 IRK 80 TOH 92 FEI 92

Neu

tron

emis

sion

cro

ss-s

ectio

n [b

/MeV

]

Secondary neutron energy [MeV]

EFF-DOC-897, EFF/EAF Monitoring Meeting, OECD/IEA Headquarters, Paris, May 10-12, 2004 16

natW(n,2n) cross-section

6,0x106 8,0x106 1,0x107 1,2x107 1,4x107 1,6x107 1,8x107 2,0x1070

1

2

W-nat(n,2n)

BRC 80 (Frehaut) FENDL-2 EFF2.4 ENDF/B-VI JENDL-3.3N

eutro

n cr

oss-

sect

ion

[bar

n]

Neutron energy [eV]

EFF-DOC-897, EFF/EAF Monitoring Meeting, OECD/IEA Headquarters, Paris, May 10-12, 2004 17

Conclusions

• JENDL-3.3 vs. FENDL-2 (=JENDL-FF)– Isotopic evaluation– Reduction of (n,2n) cross-section around 14 MeV

⇒ Better agreement for high energy flux above 12.5 MeV– Soft neutron emission spectrum

⇒ Strong underestimation of neutron flux in 1 - 5 MeV range⇒ Underestimation of fast (E> 1 MeV) neutron flux up to 25 %

(more than other available W evaluations)⇒ Overestimation of low energy neutron flux indicated

(cf. also I. Kodeli, EFF-DOC-885, November 2003)

• JENDL-3.3 W data not optimal choice for fusion applications

⇒ Improvements expected with ongoing EFF evaluation