Evidence for weak spin-orbit interaction experienced by Cooper pairs in the spin-triplet superconductor UPt; Pt-NMR study

Aoyama, Taisuke*; Kotegawa, Hisashi*; Kimura, Noriaki*; Yamamoto, Etsuji; Haga, Yoshinori; Onuki, Yoshichika*; To, Hideki*

Journal of the Physical Society of Japan, 88(6), p.064706_1 - 064706_7, 2019/06

https://doi.org/10.7566/JPSJ.88.064706

Fermi surface of ThRuSi as a reference to the strongly correlated isostructural metals investigated by quantum oscillations

Matsumoto, Yuji*; Haga, Yoshinori; Tateiwa, Naoyuki; Aoki, Haruyoshi*; Kimura, Noriaki*; Yamamura, Tomoo*; Yamamoto, Etsuji; Matsuda, Tatsuma*; Fisk, Z.*; Yamagami, Hiroshi*

Journal of the Physical Society of Japan, 85(10), p.104709_1 - 104709_7, 2016/10

https://doi.org/10.7566/JPSJ.85.104709

Enhancement of the cyclotron effective mass in UThRuSi

Haga, Yoshinori; Matsumoto, Yuji*; Tateiwa, Naoyuki; Yamamoto, Etsuji; Kimura, Noriaki*; Yamamura, Tomoo*; Fisk, Z.

Journal of Physics; Conference Series, 592(1), p.012036_1 - 012036_5, 2015/03

https://doi.org/10.1088/1742-6596/592/1/012036

Development of in-reactor observation system using Cherenkov light, 5

Otsuka, Noriaki; Takeuchi, Tomoaki; Yamamoto, Keiichi; Shibata, Akira; Kimura, Nobuaki; Takemoto, Noriyuki; Tanimoto, Masataka; Tsuchiya, Kunihiko; Sano, Tadafumi*; Unesaki, Hironobu*; et al.

KURRI Progress Report 2013, P. 215, 2014/10

http://www.rri.kyoto-u.ac.jp/PUB/report/PR/ProgRep2013/CO3.pdf#page=2

Investigation of a relation between reactor power and brightness of Cherenkov light at Kyoto University Research reactor (KUR) by a CCD camera was performed due to a development of a real-time in-core measurement technique using Cherenkov light. Analyzing the brightness value of individual RGB color component at each pixel, some of the G and B brightness values reached the maximum value of 8-bit binary number, i.e. 255, above about 2-3 MW. Therefore, we corrected the G and B brightness values by the R signals whose brightness value did not saturate even at 5 MW, the maximum reactor power of KUR. Then, the total brightness value was in proportion to the reactor power after the correction. These results indicate the reactor power can be estimated by the observation of Cherenkov light.

Single-crystal growth and de Haas-van Alphen effect study of ThRuSi

Matsumoto, Yuji*; Haga, Yoshinori; Tateiwa, Naoyuki; Aoki, Haruyoshi*; Kimura, Noriaki*; Matsuda, Tatsuma*; Yamamoto, Etsuji; Fisk, Z.; Yamagami, Hiroshi*

JPS Conference Proceedings (Internet), 3, p.011096_1 - 011096_5, 2014/06

https://doi.org/10.7566/JPSCP.3.011096

Pairing symmetry of UPt probed by thermal transport tensors

Izawa, Koichi*; Machida, Yo*; Ito, Atsushi*; So, Yoshinao*; Ota, Katsuya*; Haga, Yoshinori; Yamamoto, Etsuji; Kimura, Noriaki*; Onuki, Yoshichika; Tsutsumi, Yasumasa*; et al.

Journal of the Physical Society of Japan, 83(6), p.061013_1 - 061013_8, 2014/06

https://doi.org/10.7566/JPSJ.83.061013

Research and development of high-performance instruments for safety measure for LWRs

Takeuchi, Tomoaki; Ueno, Shunji; Komanome, Hirohisa*; Otsuka, Noriaki; Shibata, Hiroshi; Kimura, Nobuaki; Matsui, Yoshinori; Tsuchiya, Kunihiko; Araki, Masanori

Proceedings of 6th International Symposium on Material Testing Reactors (ISMTR-6) (Internet), 7 Pages, 2013/10

http://www.invap.com.ar/ismtr/images/stories/trabajos/Takeuchi-Paper.pdf

http://www.invap.com.ar/ismtr/images/stories/trabajos/Takeuchi-Presentation.pdf

During the station blackout situation at the Fukushima Dai-ichi (1F) Nuclear Power Plant, conventional in-pile instrumentation systems did not work sufficiently, resulting in the progress of the severe accident. In June 2011, the Japanese government referred to "Enhancement of instrumentation to identify the status of the reactors and PCVs" as a lesson of the accident at the 1F NPP, in the report of Japanese government to the IAEA ministerial conference in accordance with such situation, we started from 2012 a research and development which corresponds to the provisions so as to monitor the NPPs situations during a severe accident. In this research and development, we have been building of technical bases of a radiation-resistant high-definition and high-sensitivity monitoring camera, a wireless transmission system, and radiation- and heat-resistant signal line. The objective and latest progress situations of the R&D including the results of the characteristic experiments will be introduced in this symposium.

Delocalization of the electron in CeLaRuSi; The de Haas-van Alphen effect measurement

Matsumoto, Yuji; Kimura, Noriaki*; Komatsubara, Takemi*; Aoki, Haruyoshi*; Kurita, Nubuyuki*; Terashima, Taichi*; Uji, Shinya*

Journal of Physics; Conference Series, 391, p.012042_1 - 012042_4, 2012/12

https://doi.org/10.1088/1742-6596/391/1/012042

CeRuSi is a paramagnetic heavy fermion compound with the electronic specific heat coefficient of 350 mJ/mol K. When a magnetic field is applied along the [001] direction of its tetragonal ThCrSi structure, it exhibits metamagnetic transition at 7.7 T. On the other hand, when a magnetic field is applied in the (001) plane, metamagnetic transition does not occur. This magnetic anisotropy is maintained to lower Ce concentration samples. By replacing Ce with La, CeRuSi changes to antiferromagnet at 0.91 and finally to normal paramagnet of LaRuSi. In very low Ce concentration samples, the impurity Kondo effect is observed. The Kondo temperature of the = 0.02 sample is about 1 K. We have successfully observed all the dHvA oscillations in the dilute Ce concentration samples with fields in the (001) plane. Moreover, we have observed the variation of the dHvA oscillations with temperature crossing the Kondo temperature.

Development of instruments for improved safety measure for LWRs

Takeuchi, Tomoaki; Shibata, Akira; Nagata, Hiroshi; Miura, Kuniaki*; Sano, Tadafumi*; Kimura, Nobuaki; Otsuka, Noriaki; Saito, Takashi; Nakamura, Jinichi; Tsuchiya, Kunihiko

Proceedings of 5th International Symposium on Material Testing Reactors (ISMTR-5) (Internet), 8 Pages, 2012/10

http://www.murr.missouri.edu/ismtr/papercall/Papers/JAEA/Tsuchiya_ISMTR-5_instruments(Takeuchi).pdf

In-pile instrumentation systems in present LWR's are indispensable to monitor all situations during reactor operation and reactor shut down. However, those systems did not work sufficiently under the conditions of the severe accident at the Fukushima Dai-ichi (F1) Nuclear Power Plant. Based on instrumentation and irradiation experiences accumulated in JMTR, the developments of reactor instrumentation systems to prevent severe core damage accident in advance have been started. The development objects are water level gauge utilizing heating, self-powered -ray detector, hydrogen concentration gauge, and analysis system for imaging and quantification of in-reactor information using Cherenkov light.

Twofold spontaneous symmetry breaking in the heavy-fermion superconductor UPt

Machida, Yo*; Ito, Atsushi*; So, Yoshinao*; Izawa, Koichi*; Haga, Yoshinori; Yamamoto, Etsuji; Kimura, Noriaki*; Onuki, Yoshichika; Tsutsumi, Yasumasa*; Machida, Kazushige*

Physical Review Letters, 108(15), p.157002_1 - 157002_5, 2012/04

https://doi.org/10.1103/PhysRevLett.108.157002