RECENT STATUS OF NEUTRON AND GAMMA-RAY MEASUREMENTS FOR DIAGNOSTICS IN JAPAN

Kentaro OCHIAI

JAPAN ATOMIC ENERGY AGENCY

FNS

FNS

OUTLINE

Neutron measurement in JAEA/FNS Triplet coincidence TOF spectrometer Double crystal TOF spectrometer (Sasao) PPAC instruments Flash ADC system (Ishikawa) Stilbene detector (Ishikawa) Cherenkov detector (V.Yury)

Gamma-ray measurement for fast ions in JAEA/FNS D(,)6Li gamma-ray Activation method for leakage a particle

FNS

Triplet coincidence spectrometer

Some experiment of neutron spectroscopy is currently carried out in Japan (JAEA/FNS). In order to measure tritium burning ratio (DD/DT) and high resolution neutron spectrum, JAEA/FNS and Naogoya Univ. has conducted the triplet coincidence spectroscopy

Principle of triplet coincidence method Apparatus of coincident measurement

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Result and Future works

N. Naoi et al. （ Nagoya university ) will present the study on HTPD2006 May. 2006

We have obtained the energy resolution within 6% using triplet coincidence. In order to obtain the resolution within 2.5%, Some improvement will be done.

0 10 200

0.5

1

Energy (MeV)

Cou

nts

(a.u

.)

Al Light Pipe (FWHM=10.5 %)

Acrylic Light Guide (FWHM=6.0 %)

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Double crystal TOF spctroscopy

First Detector

Second Detector

Second Detector

TFA

CFD

FAN-in/out

GDG

TFA TFA

CFDD CFDD

MT

TACstop start

Delay: ~ 1nsWidth: ~ 100 ns

Range: 1 s

× 8 × 8

Lower level

0.2 V

PMT 1 PMT 2

FNS 350-keV deuteronpulsed beam 3nsec

9Be(d,n) reaction

Prof. M. Sasao will mention the detail of the experiment. So, here the present status of second detector for JT-60 diagnostics are presented.

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Result of second detector property

We obtained the TOF spectrum the second detector using by 9Be-d neutron. The efficiency, resolution and gamma effect will be obtained near D-D neutron energy.

TAC (neutron & -ray)

0100020003000400050006000700080009000

10000

350 450 550 650 750 850channel

cou

nts

/ch

an

ne

l

Gamma-flash(time~0sec)

4.16-MeV neutron

0.9-MeVneutron Gamma

3.44-MeV neutron

Neutron spectrum of second detector using by 9Be-d neutrons

2.22 and 2.59-MeV

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PPAC instruments

Experiment on an AVF-cyclotron in Tohoku-Univ.

Research of rise time of Parallel Plate Avalanche Counter (PPAC) is conducted using by heavy ion beam (AVF- Cyclotoron in Tohoku-Univ.)

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Result (PPAC)

We obtained the rise time within 3nsec. Some improvement is needed to be within 1 nsec

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D(,)6Li 2.18MeV gamma-ray

ITER D-T plasma ~ 500m3

5 x 1011 photon/sec

Target C2D2

Kobe university Tandem Van de Graaff　 accelerator, Pelletron 5SDH-2, +15 line

Nuclear properties of D(,)6Li 2.18MeV gamma-ray was researched due to the diagnostics of high energetic -particle.

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Result (D(,)6Li 2.18MeV gamma-ray)

2160 2180 2200 2220 2240 2260 2280 2300

0

20

40

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Yie

lds

co

un

ts/k

eV

/mC

2160 2180 2200 2220 2240 2260 2280 2300

0

20

40

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100

2160 2180 2200 2220 2240 2260 2280 2300

0

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2160 2180 2200 2220 2240 2260 2280 23000

2000

4000

6000

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10000

E energy keV

E= 2.25MeV

E = 3.00MeV

E = 3.50MeV

E = 4.00MeV

2222~2237

2.230~2248

2.255~2234

2.239~2260

E0=21862160 2180 2200 2220 2240 2260 2280 2300

0

20

40

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100

Yie

lds

co

un

ts/k

eV

/mC

2160 2180 2200 2220 2240 2260 2280 2300

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100

2160 2180 2200 2220 2240 2260 2280 2300

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600

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1000

2160 2180 2200 2220 2240 2260 2280 23000

2000

4000

6000

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10000

E energy keV

E= 2.25MeV

E = 3.00MeV

E = 3.50MeV

E = 4.00MeV

2222~2237

2.230~2248

2.255~2234

2.239~2260

E0=21862160 2180 2200 2220 2240 2260 2280 2300

0

20

40

60

80

100

Yie

lds

co

un

ts/k

eV

/mC

2160 2180 2200 2220 2240 2260 2280 2300

0

20

40

60

80

100

2160 2180 2200 2220 2240 2260 2280 2300

0

200

400

600

800

1000

2160 2180 2200 2220 2240 2260 2280 23000

2000

4000

6000

8000

10000

E energy keV

E= 2.25MeV

E = 3.00MeV

E = 3.50MeV

E = 4.00MeV

2222~2237

2.230~2248

2.255~2234

2.239~2260

E0=2186

Yie

lds

coun

ts/k

eV/m

C

MeV186.2,

cos100

E

c

vEE Li

We obviously obtained the photo peak of the gamma and energy dependence.It was found that energy dependency was different from the past data.

Photo peak of D(a,g)6Li 2.18MeV gamma-rayEnergy dependency of gamma yield

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Activation method for lost particle

Irradiated CaF2 sample

19F+a→n + 22Na

1274 keV

511keV

3.5-MeV He++ implantation

K-40

Future works • Property of Irradiation of DT neutron• Property of Irradiation of fast ions• Experiment in JT-60 • How to insert the CaF2 into ITER

Activation method by 19F(,n)22Na reaction has been started to measure lost particle