Large trigonal-field effect on spin-orbit coupled states in a pyrochlore iridate

Uematsu, Daisuke*; Sagayama, Hajime*; Arima, Takahisa*; Ishikawa, Jun*; Nakatsuji, Satoru*; Takagi, Hidenori*; Yoshida, Masahiro*; Mizuki, Junichiro; Ishii, Kenji

Physical Review B, 92(9), p.094405_1 - 094405_6, 2015/09

https://doi.org/10.1103/PhysRevB.92.094405

XUV-FEL spectroscopy; He two-photon ionization cross-sections

Sato, Takahiro*; Iwasaki, Atsushi*; Ishibashi, Kazuki*; Okino, Tomoya*; Yamanouchi, Kaoru*; Adachi, Junichi*; Yagishita, Akira*; Yazawa, Hiroki*; Kannari, Fumihiko*; Aoyama, Makoto; et al.

Europhysics News, 42(5), P. 10, 2011/09

The resonant and non-resonant two-photon single ionization processes of He were investigated using intense free electron laser light in the extreme ultraviolet (XUV) region (53.4-61.4 nm) covering the 1s-2p and 1s-3p resonant transitions of He. On the basis of the dependences of the yield of He on the XUV light-field intensity at 53.4, 58.4, 56.0 and 61.4 nm, the absolute values of the two-photon ionization cross sections of He at the four different wavelengths and their dependence on the light-field intensity were determined for the first time.

Study on effects of swift heavy ion irradiation in cerium dioxide using synchrotron radiation X-ray absorption spectroscopy

Ono, Hirotaka*; Iwase, Akihiro*; Matsumura, Daiju; Nishihata, Yasuo; Mizuki, Junichiro; Ishikawa, Norito; Baba, Yuji; Hirao, Norie; Sonoda, Takeshi*; Kinoshita, Motoyasu

Nuclear Instruments and Methods in Physics Research B, 266(12-13), p.3013 - 3017, 2008/06

https://doi.org/10.1016/j.nimb.2008.03.155

Radiation damage of CeO irradiated with 200MeV Xe is characterized by EXAFS and XPS measurement. It is found that oxygen deficiencies are created after the irradiation, and charge state of Ce is changed from +4 to +3.

Study on effects of heavy ion irradiation on CeO by using synchrotron radiation X-ray absorption spectroscopy; As a simulation study for radiation damage in high-burnup light water reactor fuels

Ono, Hirotaka*; Matsumura, Daiju; Nishihata, Yasuo; Mizuki, Junichiro; Ishikawa, Norito; Sonoda, Takeshi*; Kinoshita, Motoyasu*; Iwase, Akihiro*

Materials Research Society Symposium Proceedings, Vol.1043, p.179 - 183, 2008/00

CeO thin films were irradiated with 200 MeV Xe ions. Effects of the irradiation were studied by using Extended X-ray Absorption Fine Structure (EXAFS) measurement at SPring-8 synchrotron radiation facility. EXAFS spectra for the irradiated thin films near the Ce K-edge show that the coordination number for oxygen atoms around Ce atom decreases and that the Ce-O Debye-Waller factor increases by the irradiation. The atomic distance between oxygen atom and Ce atom does not vary within the accuracy of EXAFS measurement. The effect of high density electronic excitation on the structure of CeO is discussed.

Development of a real-time thermal neutron monitor and its clinical application

Ishikawa, Masayori*; Ono, Koji*; Matsumura, Akira*; Yamamoto, Tetsuya*; Hiratsuka, Junichi*; Miyatake, Shinichi*; Kato, Itsuro*; Sakurai, Yoshinori*; Kobayashi, Toru*; Kumada, Hiroaki; et al.

Proceedings of 12th International Congress on Neutron Capture Therapy (ICNCT-12), p.397 - 400, 2006/10

An ultraminiature thermal neutron monitor which was named SOF detector (Scintillator with Optical Fiber detector) had been developed for BNCT treatment. We had been experienced 15 clinical trials using SOF detector until the end of 2005, some measurements got good results, and some got unacceptable results. One reason of the unacceptable results was due to dislocation of the detector during treatment. This is because it is difficult to fix the SOF detector on patient's skin without strong sticker. To overcome this problem, a loop-type SOF probe was developed. By using the loop-type SOF detector, fixing on the patient's skin was much easier.

Development of a wide-range paired scintillator with optical fiber neutron monitor for BNCT irradiation field study

Ishikawa, Masayori*; Kumada, Hiroaki; Yamamoto, Kazuyoshi; Kaneko, Junichi*; Bengua, G.*; Unesaki, Hironobu*; Sakurai, Yoshinori*; Tanaka, Kenichi*; Kosako, Toshiso*

Nuclear Instruments and Methods in Physics Research A, 551(2-3), p.448 - 457, 2005/10

https://doi.org/10.1016/j.nima.2005.06.044

A wide range thermal neutron detector was developed based on the Scintillator with Optical Fiber (SOF) detector which has been previously used for thermal neutron monitoring during boron neutron capture therapy irradiation. With this new detector system we intended to address the issues of real-time thermal neutron flux measurement and the simultaneous measurement of a wide range of thermal neutron flux in a BNCT irradiation field which were difficult to implement with the gold wire activation method. A good agreement between the thermal neutron flux measured by the gold wire activation method and the paired SOF detector system was observed. However, measurements which would normally take a few days to perform with the gold wire activation method were obtained in just about 15 min using the SOF detector system. We also confirmed the dynamic range of linearity for the SOF detector system to be in the order of magnitude of 1e-4.

Fabrication of saturated temperature capsule for IASCC study

Ishikawa, Kazuyoshi; Kikuchi, Taiji; Isozaki, Futoshi*; Inoue, Hiromi; Oba, Toshihiro; Matsui, Yoshinori; Saito, Takashi; Nakano, Junichi; Tsuji, Hirokazu

JAERI-Tech 2002-061, 69 Pages, 2002/08

JAERI-Tech-2002-061.pdf:12.21MB

Study of irradiation assisted stress corrosion cracking (IASCC) is an important subject for the plant life assessment and extension of the light water reactors (LWRs). It is necessary that initiation mechanism of IASCC should be made clear under combined effect of irradiation, environment and stress in order to understand IASCC phenomena. Under the existing circumstance, Saturated Temperature Capsule (SATCAP) were fabricated for the irradiation test of IASCC studies in Japan Material Testing Reactor (JMTR). SATCAP is the irradiation rig to irradiate materials in high pressure water of controlled chemistry and temperature simulating Boiling water reactors (BWRs) core environment from the new water feelding system of out-of-pile. This report describes (1) investigation of technical problems for the design and fabrication of SATCAP, (2) the tests results of the problems and (3) fabrication and inspection of SATCAP.

None

*; *; *

JNC TJ8420 2000-014, 531 Pages, 2000/03

JNC-TJ8420-2000-014.pdf:20.54MB

no abstracts in English

Libraries based on JENDL-3.2 for ORIGEN2 code; ORLIBJ32

Suyama, Kenya; Katakura, Junichi; Okawachi, Yasushi*; Ishikawa, Makoto*

JAERI-Data/Code 99-003, 83 Pages, 1999/02

JAERI-Data-Code-99-003.pdf:3.47MB

no abstracts in English

Fine magnetic structure induced by high-energy ion irradiation in Fe-Rh alloy

Ishikawa, Norito; Kawasuso, Atsuo; Takagaki, Masafumi*; Suzuki, Motohiro*; Mizuki, Junichiro; Zushi, Yoshihiro*; Fujita, Naoki*; Hori, Fuminobu*; Seki, Shuhei*; Tsukuda, Satoshi*; et al.

no journal, , 

It is already found that magnetic transition temperature of Fe-50at.%Rh changes by high-energy ion irradiation. This irradiation-induced changes in magnetic properties has been investigated by magnetic force microscopy. It has been found that microscopic magnetic structure appears after ion-irradiation, and the structure changes depending on the ion-fluence. The observed structure was not the same as that observed for Fe-rich ferromagnetic Fe-45at.%Rh alloys.