実験報告書様式（CROSS 開発課題）

Experimental Report

承認日 Date of Approval 2014/4/25
承認者 Approver Ryoichi Kajimoto
提出日 Date of report 2014/4/25

実験課題番号 Project No.

装置責任者 Name of Instrument scientist

2013I0101

Ryoichi Kajimoto

実験課題名 Title of experiment

装置名 Name of Instrument/（BL No.）

Improvement of the Performance of 4SEASONS to Provide an

BL01 4SEASONS

Advanced Experimental Environments for Users

利用期間 Dates of experiments

実験責任者名 Name of principal investigator

2013/04/01 09:00 – 2013/04/03 09:00

Kazuhiko Ikeuchi (for Sundgae Ji, PI)

2013/05/16 11:00 – 2013/05/17 11:00所属 Affiliation

2014/02/20 11:00 – 2014/02/21 11:00

CROSS-TOKAI

2014/04/03 11:00 – 2014/04/05 11:00

１．研究成果概要（試料の名称、組成、物理的・化学的性状を明記するとともに、実験方法、利用の結果得られた主なデータ、考察、結論、図表等を記述してください。
Outline of experimental results (experimental method and results should be reported including sample
information such as composition, physical and/or chemical characteristics.
BL01 4SEASONS, the Fermi chopper spectrometer, has been undergoing scientificcommissioning and hosting users in various scientific fields. As the CROSS R&D project in 2013,
we performed the subjects about (1) Energy & Momentum transfer dependence of resolutionfunction, (2) Numerical test for measurement with the 7T magnet, (3) Feasibility test of newmaterials. The results will be returned to users as detailed and quantitative experimental data.
(1) Energy & Momentum transfer dependence of resolution function
An instrumental resolution function is necessary to compare calculation such as magnon(phonon) dispersion and intensities with experiment. However, energy and Q resolutions of4SEASONS

had

not

been

investigated sufficiently. Therefore,to check experimentally whether
analytically calculated resolutions of4SEASONS are reasonable or not isimportant. For the energy-resolution
measurement, commercial powder
C4H2I2S was used, while for theQ-resolution

measurement,

polycrystalline Al2O3 was used. As
shown in Figure, we figured out thatexperimental resolutions obtained byfitting ħω- and Q-dependences of theFig. 1. Left panel : Energy transfer dependence of theenergy resolution. Right panel : Momentum transfer
dependence of the momentum resolution at ħω = 0
meV. Both were obtained for many Ei’s utilized in themultiEi method. Lines are calculated energy/momentumresolutions for each Ei [1].

１．研究成果概要（つづき） Outline of experimental results (continued).
scattered neutron intensities are well reproduced by analytically calculated resolutions for wideranges of ħω, Q, and incident neutron energy at 4SEASONS. We published this result in JPS

Conference Proceedings [1].
(2) Numerical test for measurementwith 7T magnet
In advance of online operation of 7
T magnet at BL01 4SEASONS, weevaluated magnetic field distribution
caused by the operation numerically.
Accordingtothenumericalsimulation, an applied field of 1 T
causes a magnetic field of 15 G
around a turbo molecular pump

Fig. 1. Left panel : Visualized map of magnetization of
the vacuum chamber due to H = 7 T operation. Rightpanel : Field dependence of the residual magnetizationon the flame.

installed just below the sample
position of the spectrometer. In addition, as shown in Fig. 2, an applied field also magnetizes Fe
flame of the spectrometer and causes a residual field of 32 G by 7 T, and of 5 G by 1 T at the sample
position. Based on the result, we will plan an experiment with magnet after careful consideration
to protect BL items and the possibility of the polarization experiment.
(3) Feasibility test of new materials(3-1) A Li-ion battery is the most promising battery as a commercial storage battery. Thus, toinvestigate the Li diffusion in the positive electrode of the battery such as LiCoO2 and LiMn2O4,
many quasi-elastic neutron scattering experiments at BL02 and diffraction measurements at
BL08 are performed in J-PARC so far. Such measurements, however, only cover the reciprocal
space near ħω = 0, and no measurement over the wide range of the reciprocal space has been
performed. Here, we have performed inelastic neutron scattering measurements on LiCoO2 using

Ei = 100 meV neutrons, and we succeeded in measuring the phonon in LiCoO2 in the wide range oftemperature and the reciprocal space. We are now analyzing how the phonon affects the bulk
properties in LiCoO2.
(3-2) In order to verify, how high energy BL01 can approach at low Q side, we carried out a test
measurement for YBaFe4O7 which shows a streak-like magnetic excitation at Q~1.25Ǻ-1 with dQ~1Ǻ-1 width (HWHM). As a result, we could observe the streak unambiguously up to ħω~80meV(with a trace up to 100meV).
[1] K. Iida et al., JPS Conf. Proc. 1 (2014) 014016.
必要に応じて、A4 サイズの用紙に続きを記入して下さい。
Please use A4-size papers for further reporting, if necessary.