実験報告書様式（一般利用課題・成果公開利用）（ ※本報告書は英語で記述してください。ただし、産業利用課題として採択されている方は日本語で記述していただいても結構です。 ）MLF Experimental Report

提出日 Date of Report

課題番号 Project No.

装置責任者 Name of responsible person

2012A0086

Kenichi Oikawa

実験課題名 Title of experiment

装置名 Name of Instrument/（BL No.）

Development of neutron spin phase contrast imaging technique at

BL10a pulsed neutron source

実施日 Date of Experiment

実験責任者名 Name of principal investigator2012/06/23-2012/06/25

Hirotoshi Hayashida
所属 Affiliation
J-PARC Center, JAEA
試料、実験方法、利用の結果得られた主なデータ、考察、結論等を、記述して下さい。（適宜、図表添付のこと）Please report your samples, experimental method and results, discussion and conclusions. Please add figures andtables for better explanation.
1. 試料 Name of sample(s) and chemical formula, or compositions including physical form.
Solenoid coil with aluminum wire was used as a test sample of this experiment. The
picture of the coil is shown in fig. 1-1.

Fig. 1-1. The pictureof the test sample.

2. 実験方法及び結果 （実験がうまくいかなかった場合、その理由を記述してください。）
Experimental method and results.

If you failed to conduct experiment as planned, please describe reasons.

A neutron spin phase contrast (NSPC) imaging
method is one of the effective methods to visualize
magnetic domains in magnetic materials. The aimof this experiment was applying the NSPC
imaging method to a pulsed neutron source.
The NSPC consists of polarizer, two /2 flippers
and analyzer. A guide magnetic field is applied
from the polarizer to the analyzer in order to avoid
a depolarization of neutron spins. Figure 2-1
shows a schematic view and picture of the setup ofNSPC method at BL-10 NOBORU.

Fig. 2-1. The schematic diagram and picture of NSPCsetup at BL-10.
12. 実験方法及び結果（つづき） Experimental method and results (continued)
Since a Mezei-type of spin flipper is effective to work as /2 condition, the Mezei flipper is used in the NSPC
method. However, the Mezei flipper works for a monochromatic neutron beam in generally, because aLarmor-precession angle of neutron spin depends on a velocity of neutron. Since the neutron velocity v at theflipper is given by v = L/t, where L is the distance from the neutron source to the Mezei-flipper and t is the timeof flight, strength of the magnetic field of the Mezei-flipper have to be applied with 1/t decay in order to apply
the Mezei-flipper to pulsed neutron. In this experiment, two /2 flippers were driven with TOF mode explained
above.
Figure 2-2, 2-3 and 2-4 shows a result of the NSPC signal measured at BL-10 NOBORU. Solenoid coil withaluminum wire was used as a test sample. Magnetic field of the solenoid coil was varied by changing a current
applied to the solenoid coil. The magnetic field generated by the solenoid coil affects to the precession angle ofneutron spin and this changes a cycle of the NSPC signal. Figure 2-2 and figure 2-3 correspond to the NSPC
signal with the current of 0 A and 0.5 A, respectively. These results show a difference of the cycle of NSPC
signal caused by the magnetic field generated by the solenoid coil. Figure 2-4 shows a 3-dimentional figure ofthe NSPC signal. This figure also shows that the cycle of the NSPC signal varies with changing the current.
An experiment applying the NSPC to the pulsed neutron source was successfully performed and expected

1.0

1.00.80.8
Visibility

Visibility

results are obtained.

0.6
0.4

0.6
0.4

0.2

0.2

0.0

0.0
2030

4050
60
TOF / 0.5msec

7080

20Fig. 2-2. NSPC signal with the current of 0 A.

30405060
TOF / 0.5msec

70Fig. 2-3. NSPC signal with the current of 0 A.

Fig. 2-4. 3D figure of the NSPC signal.

280