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1. Recent progress of JT-60SA project toward plasma operation

Author

H. Shirai, K. Takahashi, E. Di Pietro, D. Abate, W. Abdel Maksoud, H. Abe, N. Aiba, T. Abe, M. Akimitsu, J. Ayllon-Guerola, T. Arai, J.-F. Artaud, N. Asakura, N. Ashikawa, L. Balbinot, P. Barabaschi, O. Baulaigue, E. Belonohy, A. Belpane, W. Bin, F. Bombarda, T. Bolzonella, F. Bonne, M. Bonotto, J. Botija, J. Buermans, S. Cabrera-Pérez, A. Cardella, D. Carralero, L. Carraro, J. Cavalier, M. Cavinato, M. Chernyshova, S. Chiba, S. Clement-Lorenzo, V. Cocilovo, S. Coda, R. Coelho, I. Coffey, B. Collin, V. Corato, A. Cucchiaro, T. Czarski, M. Dairaku, S. Davis, C. Day, E. Dela Luna, G. De Tommasi, P. Decool, L. Di Pace, M. Dibon, G. Disset, F. D’Lsa, A. Ejiri, Y. Endo, N. Ezumi, G. Falchetto, A. Fassina, P. Fejoz, A. Ferro, W. Fietz, L. Figini, T. Fornal, G. Frello, T. Fujita, T. Fukuda, K. Fukui, M. Fukumoto, H. Funaba, M. Furukawa, S. Futatani, L. Gabellieri, E. Gaio, K. Galazka, J. Garcia, J. Garcia-Dominguez, J. Garcia-Lopez, M. Garcia-Munoz, L. Garzotti, F. Gasparini, S. Gharafi, L. Giacomelli, G. Ginoulhiac, G. Giruzzi, L. Giudicotti, J. Gonzalez-Martin, R. Guillén-González, N. Hajnal, S. Hall, K. Hamada, K. Hanada, M. Hanada, K. Hasegawa, S. Hatakeyama, V. Hauer, N. Hayashi, T. Hayashi, R. Heller, J. Hidalgo-Salaverri, S. Higashijima, J. Hinata, S. Hiranai, J. Hiratsuka, R. Hiwatari, C. Hoa, H. Homma, A. Honda, M. Honda, K. Hoshino, H. Hurzlmeier, M. Iafrati, K. Ibano, H. Ichige, M. Ichikawa, M. Ichimura, K. Ida, S. Ide, H. Idei, M. Iguchi, T. Iijima, S. Iio, R. Ikeda, Y. Ikeda, T. Imai, R. Imazawa, S. Inagaki, M. Inomoto, S. Inoue, A. Isayama, S. Ishida, Y. Ishii, M. Isobe, F. Janky, E. Joffrin, A. Jokinen, S. Kado, S. Kajita, K. Kajiwara, Y. Kamada, I. Kamata, A. Kaminaga, K. Kamiya, D. Kanapienyte, Y. Kashiwa, M. Kashiwagi, K. Katayama, Y. Kawamata, G. Kawamura, K. Kawano, Y. Kazakov, K. Kimura, F. Kin, M. Kisaki, S. Kitajima, K. Kiyono, K. Kizu, Y. Ko, K. Kobayashi, M. Kobayashi, S. Kobayashi, Ta. Kobayashi, To. Kobayashi, G. Kocsis, A. Kojima, S. Kokusen, M. Komata, K. Komuro, S. Konishi, A. Kovacsik, I. Ksiazek, M. Kubkowska, G. Kühner, M. Kuramochi, K. Kurihara, T. Kurki-Suonio, A.B. Kurniawan, T. Kuwata, B. Lacroix, V. Lamaison, A. Lampasi, P. Lang, P. Lauber, K. Lawson, Q. LeCoz, A. Louzguiti, R. Maekawa, T. Maekawa, S. Maeyama, G. Maffia, P. Maget, J. Mailloux, I. Maione, A. Maistrello, K. Malinowski, A. Mancini, G. Marchiori, J.-L. Marechal, V. Massaut, S. Masuzaki, R. Matoike, G. Matsunaga, S. Matsunaga, A. Matsuyama, Ch Mayri, M. Mattei, M. Medrano, A. Mele, I. Meyer, F. Michel, T. Minami, Y. Miyata, J. Miyazawa, Y. Miyo, T. Mizuuchi, K. Mogaki, J. Morales, P. Moreau, T. Morisaki, S. Morishima, S. Moriyama, A. Moro, H. Murakami, M. Murayama, S. Murakami, K. Nagasaki, O. Naito, N. Nakamura, S. Nakamura, T. Nakano, Y. Nakashima, V. Nardino, E. Narita, Y. Narushima, K. Natsume, S. Nemoto, R. Neu, S. Nicollet, M. Nishikawa, S. Nishimura, T. Nishitani, M. Nishiura, T. Nishiyama, M. Nocente, Y. Nobuta, L. Novello, F. Nunio, S. Ochoa, K. Ogawa, T. Ogawa, Y. Ogawa, S. Ohdachi, Y. Ohmori, N. Ohno, Y. Ohtani, K. Ohtsu, M. Ohzeki, T. Oishi, J. Okano, K. Okano, Y. Onishi, M. Osakabe, T. Oshima, V. Ostuni, A. Owada, M. Oya, Y. Oya, T. Ozeki, M.M. Parody Guzmán, R. Pasqualotto, S. Pelli, E. Perelli, E. Peretti, G. Phillips, C. Piccinni, L. Pigatto, A. Pironti, A. Pizzuto, B. Plöckl, G. Polli, J.-M. Poncet, P. Ponsot, G. Pucella, M. Puiatti, D. Radloff, V. Raimondi, F. Ramos, P. Rancsik, D. Ricci, S. Ricciarini, N. Richermoz, E. Rincon, A. Romano, P. Rossi, P. Roussel, G. Rubino, H. Saeki, A. Sagara, S. Sakakibara, H. Sakamoto, Miki Sakamoto, Mizu Sakamoto, Y. Sakamoto, A. Sakasai, S. Sakata, R. Sakurai, B. Salanon, A. Salmi, G. Sannazzaro, R. Sano, A. Sanpei, T. Sasajima, S. Sasaki, H. Sasao, F. Sato, M. Sato, T. Sato, M. Sawahata, A. Scherber, S. Scully, J. Segado-Fernandez, M. Seki, N. Seki, S. Seki, Y. Shibama, Y. Shibata, T. Shikama, K. Shimada, M. Shimono, J. Shinde, T. Shinya, K. Shinohara, J. Shiraishi, S. Soare, A. Soleto, Y. Someya, S. Sonoda, C. Sozzi, E. Streciwilk-Kowalska, H. Strobel, M. Sueoka, A. Sukegawa, S. Sumida, H. Suzuki, Ma Suzuki, Mi Suzuki, S. Suzuki, T. Suzuki, Y. Suzuki, J. Svoboda, T. Szabolics, T. Szepesi, Y. Takase, M. Takechi, K. Takeda, Y. Takeiri, H. Takenaga, C. Taliercio, N. Tamura, Hiro Tanaka, Hito Tanaka, K. Tanaka, Y. Tanaka, K. Tani, H. Tanigawa, M. Tardocchi, A. Terakado, M. Terakado, T. Terakado, B. Teuchner, B. Tilia, H. Tobari, H. Tobita, K. Tobita, K. Toi, N. Toida, H. Tojo, M. Tokitani, T. Tokuzawa, V. Tormarchio, M. Tomine, A. Torre, T. Totsuka, K. Tsuchiya, N. Tsujii, D. Tsuru, H. Tsutsui, M. Uchida, Y. Ueda, J. Uno, H. Urano, K. Usui, H. Utoh, M. Valisa, M. Vallar, R. Vallcorba-Carbonel, J.-C. Vallet, J. Varela, J. Vega, M. Verrecchia, L. Vieillard, F. Villone, P. Vincenzi, K. Wada, R. Wada, T. Wakatsuki, M. Wanner, F. Watanabe, K. Watanabe, S. Watanabe, T. Wauters, S. Wiesen, M. Wischmeier, M. Yagi, J. Yagyu, M. Yajima, S. Yamamoto, H. Yamanaka, K. Yamauchi, Y. Yamauchi, H. Yamazaki, K. Yamazaki, R. Yamazaki, S. Yamoto, S. Yanagi, K. Yanagihara, S. Yokooka, M. Yokoyama, T. Yokoyama, M. Yoshida, M. Yoshimura, N. Yoshizawa, K. Yuinawa, L. Zani, and P. Zito

Subjects
JT-60SA, superconducting tokamak, risk mitigation measures, integrated commissioning, maintenance and enhancement, international collaboration, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

Superconducting (SC) tokamak JT-60SA plays an essential role in fusion research and development by supporting and complementing the ITER project, providing directions to the DEMO design activity and fostering next generation scientists and engineers. Since the short circuit incident at the terminal joints of equilibrium field coil #1 during the integrated commissioning (IC) in March 2021, both EU and JA implementing agencies (IAs) have examined how to ensure safe operation of JT-60SA by mitigating the risk of possible discharge occurrence inside the cryostat. Based on the experience of the global Paschen tests, the IAs have established a strategy of risk mitigation measures, which is a combination of (i) reinforcement of insulation, (ii) avoiding unnecessary voltage application to the coil systems and (iii) immediate de-energization of the coils when deteriorated vacuum conditions are detected. Thanks to the considerable efforts of the Integrated Project Team members, the IC restarted in May 2023. After confirmation of the SC state of the coil systems (TF, EF and CS), the coil energization test and the plasma operation phase 1 (OP-1) started. The first plasma was successfully achieved on 23 October 2023 with a limited value of voltage and current applied to the coils. The plasma configuration control was also confirmed with low plasma current and low auxiliary heating power conditions. Based on the IO–F4E–QST collaboration, activities of JT-60SA have been shared with the IO and provided an important lesson for ITER assembly and commissioning, and will provide an outstanding contribution to fusion research at large. After OP-1, maintenance & enhancement phase 1 (M/E-1) starts from January 2024, in which in-vessel components are installed, and heating and diagnostic systems are extensively upgraded to allow a high power heating experiment planned in OP-2. In order to make the best use of JT-60SA, a newly organized JT-60SA experiment team will refine the research plan for the future high heating power operation phase.

Published
2024
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2. Development of a method for analyzing the positional correlation of local structures in scanning probe microscopy images using template-matching image-processing method

Author

Sota Tsubokura, Shoya Kawano, Yumiko Imai, Tadashi Ueda, Kei-ichi Nakamoto, Haruo Noma, Hirohisa Hioki, and Taketoshi Minato

Subjects
scanning probe microscopy, atomic force microscopy, scanning tunneling microscopy, surface, interface, image processing, Physics, QC1-999
Abstract

The functionalities of materials are governed by the atom type and arrangement, and perturbations caused by defects and adsorbate interactions often significantly alter the behavior of materials. Scanning probe microscopy (SPM) can capture complex interactions caused by the structures on surfaces. It is, however, difficult to analyze such interactions appearing there. In this paper, an image-processing technique that employs template matching to recognize local structures in SPM images and calculate positional correlations is reported. This approach opens new avenues for investigating intricate perturbations in the sciences and provides detailed insights into materials science.

Published
2024
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3. Systematic Search for Water Fountain Candidates Using the Databases of Circumstellar Maser Sources

Author

Haichen Fan, Jun-ichi Nakashima, D. Engels, Yong Zhang, Jian-Jie Qiu, Huan-Xue Feng, Jia-Yong Xie, Hiroshi Imai, and Chih-Hao Hsia

Subjects
Circumstellar envelopes, Circumstellar masers, Asymptotic giant branch, Post-asymptotic giant branch stars, Astrophysics, QB460-466
Abstract

Water fountains (WFs) are thought to be objects in the morphological evolution of the circumstellar envelopes of low- and intermediate-mass evolved stars, transitioning from spherically symmetric to asymmetric shapes. We used databases of circumstellar 1612 MHz OH and 22.235 GHz H _2 O maser sources to search for new WF candidates using the criterion of a larger velocity range of the H _2 O maser emission compared to that of the OH maser emission. Thus, it is in principle possible to identify WFs with H _2 O velocity ranges smaller than those for the previously known WFs. For the OH maser line, we analyzed database entries of 8474 observations from 2195 sources, and 6085 observations from 3642 sources for the H _2 O maser line. After a close examination of the velocity ranges and line profiles, we identified 11 sources that meet the criterion mentioned above. We examined the IRAS colors of the selected sources and found that two of them (IRAS 19069+0916 and IRAS 19319+2214) are in the color region for post-AGB stars. We find that the maser velocity criterion can discover other astrophysically interesting objects than just WFs. Such objects may include peculiar planetary nebulae with maser emissions and stellar merger remnants.

Published
2024
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10. Evolution of the Outflow in the Water Fountain Source IRAS 18043–2116

Author

L. Uscanga, H. Imai, J. F. Gómez, D. Tafoya, G. Orosz, T. P. McCarthy, Y. Hamae, and K. Amada

Subjects
Water masers, Asymptotic giant branch stars, Astrophysical masers, Post-asymptotic giant branch stars, Stellar jets, Astrophysics, QB460-466
Abstract

We present the spectral and spatial evolution of H _2 O masers associated with the water fountain source IRAS 18043−2116, found in observations with the Nobeyama 45 m Telescope and the Australia Telescope Compact Array. We have found new highest-velocity components of the H _2 O masers (at the redshifted side V _LSR ≃ 376 km s ^−1 and at the blueshifted side V _LSR ≃ −165 km s ^−1 ), and the resulting velocity spread of ≃540 km s ^−1 breaks the speed record of fast jets/outflows in this type of sources. The locations of those components have offsets from the axis joining the two major maser clusters, indicating a large opening angle of the outflow (∼60°). The evolution of the maser cluster separation of ∼2.9 mas yr ^−1 and the compact (∼0.″2) CO emission source mapped with the Atacama Large Millimeter-submillimeter Array suggest a very short (∼30 yr) timescale of the outflow. We also confirmed an increase in the flux density of the 22 GHz continuum source. The properties of the jet and the continuum sources and their possible evolution in the transition to the planetary nebula phase are further discussed.

Published
2023
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11. Self-assembling formation of Si-QDs on SiO2 line patterns.

Author

Tsuji, Ryoya, Imai, Yuki, Baek, Jongeun, Makihara, Katsunori, and Miyazaki, Seiichi

Abstract

The lateral growth of Si-quantum dots (QDs) on line-patterned SiO2 from the thermal decomposition of pure monosilane (SiH4) has been systematically examined. We confirmed that the Si-QDs diameter in the line direction of the SiO2 patterns has the same growth rate as the SiO2 thin film surface without the line patterns. Moreover, it has been found that in the growth of Si-QDs in the width direction, a surface migration of Si precursors adsorbed from space regions could contribute to dots growth on line-patterned SiO2, which results in an elliptical growth. Furthermore, we have demonstrated a one-dimensional arrangement of highly dense-elliptical shaped Si-QDs with high uniformity in size by controlling line width, CVD time, and temperature. [ABSTRACT FROM AUTHOR]

Published
2024
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15. Evolution of the Outflow in the Water Fountain Source IRAS 18043–2116

Author

Ministerio de Ciencia e Innovación (España), European Research Council, European Commission, Universidad de Guanajuato, Japan Society for the Promotion of Science, Australian Research Council, National Key Research and Development Program (China), Uscanga, L., Imai, H., Gómez Rivero, José Francisco, Tafoya, D., Orosz, G., McCarthy, T. P., Hamae, Y., Amada, K., Ministerio de Ciencia e Innovación (España), European Research Council, European Commission, Universidad de Guanajuato, Japan Society for the Promotion of Science, Australian Research Council, National Key Research and Development Program (China), Uscanga, L., Imai, H., Gómez Rivero, José Francisco, Tafoya, D., Orosz, G., McCarthy, T. P., Hamae, Y., and Amada, K.

Abstract

We present the spectral and spatial evolution of H2O masers associated with the water fountain source IRAS 18043−2116, found in observations with the Nobeyama 45 m Telescope and the Australia Telescope Compact Array. We have found new highest-velocity components of the H2O masers (at the redshifted side VLSR ≃ 376 km s−1 and at the blueshifted side VLSR ≃ −165 km s−1), and the resulting velocity spread of ≃540 km s−1 breaks the speed record of fast jets/outflows in this type of sources. The locations of those components have offsets from the axis joining the two major maser clusters, indicating a large opening angle of the outflow (∼60°). The evolution of the maser cluster separation of ∼2.9 mas yr−1 and the compact (∼0farcs2) CO emission source mapped with the Atacama Large Millimeter-submillimeter Array suggest a very short (∼30 yr) timescale of the outflow. We also confirmed an increase in the flux density of the 22 GHz continuum source. The properties of the jet and the continuum sources and their possible evolution in the transition to the planetary nebula phase are further discussed. © 2023. The Author(s). Published by the American Astronomical Society.

Published
2023

18. Inhomogeneous superconductivity in thin crystals of FeSe1−xTex (x = 1.0, 0.95, and 0.9)

Author

Ritsuko Eguchi, Megumi Senda, Eri Uesugi, Hidenori Goto, Akihiko Fujiwara, Yasuhiko Imai, Shigeru Kimura, Takashi Noji, Yoji Koike, and Yoshihiro Kubozono

Subjects
iron-based superconductor, thin crystals, microbeam XRD, Materials of engineering and construction. Mechanics of materials, TA401-492, Chemical technology, TP1-1185
Abstract

We investigated the temperature dependence of resistivity in thin crystals of FeSe _1−x Te _x (x = 1.0, 0.95, and 0.9), though bulk crystals with 1.0 ≧ × ≧ 0.9 are known to be non-superconducting. With decreasing thickness of the crystals, the resistivity of x = 0.95 and 0.9 decreases and reaches zero at a low temperature, which indicates a clear superconducting transition. The anomaly of resistivity related to the structural and magnetic transitions completely disappears in 55- to 155-nm-thick crystals of x = 0.9, resulting in metallic behavior in the normal state. Microbeam x-ray diffraction measurements were performed on bulk single crystals and thin crystals of FeSe _1−x Te _x . A significant difference of the lattice constant, c , was observed in FeSe _1−x Te _x , which varied with differing Te content (x), and even in crystals with the same x, which was mainly caused by inhomogeneity of the Se/Te distribution. It has been found that the characteristic temperatures causing the structural and magnetic transition ( T _t ), the superconducting transition ( T _c ), and the zero resistivity ( T _c ^zero ) are closely related to the value of c in thin crystals of FeSe _1−x Te _x .

Published
2020
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19. Nanoscale mapping of ZnO–TiO2 up-conversion phosphor containing Yb3+ and Er3+

Author

Toshihiro Nonaka, Takahito Imai, Takahiko Ban, and Shin-Ichi Yamamoto

Subjects
Zn2TiO4, Yb2Ti2O7, Er2Ti2O7, TiO2, metal organic decomposition, Materials of engineering and construction. Mechanics of materials, TA401-492, Chemical technology, TP1-1185
Abstract

Up-conversion phosphors have attracted considerable attention for their visible-light emission. In this study, a ZnO–TiO _2 up-conversion phosphor containing Yb ^3+ and Er ^3+ ions was prepared; its emission characteristics and crystal structure were analyzed, and its nanoscale elemental mapping was examined. The metal organic decomposition (MOD) method was used to fabricate the samples. After firing the sample at 1000 °C, the emission intensity showed a maximum when the molar ratio was Ti/Zn/Yb/Er = 1/1/0.06/0.02. Finally, the function of each element was considered from the viewpoint of the crystal structure and nanoscale mapping.

Published
2020
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21. Electronic band engineering of Mg2Si by isoelectronic impurity doping: a first-principles study for enhancing thermoelectric properties

Author

Kiyoka Imai, Ryohei Ikebuchi, Naomi Hirayama, Noriaki Hamada, and Yoji Imai

Subjects
General Engineering, General Physics and Astronomy
Abstract

Previous theoretical studies have suggested novel approaches for enhancing the thermoelectric performance of Mg2Si, i.e. electronic band engineering based on tensile strain to enhance the Seebeck coefficient and electrical conductivity simultaneously. To realise this approach, we investigated the doping with isoelectronic impurities (Ca, Sr, and Ba) substituted at Mg sites. We performed variable-cell relaxation calculations for Ca-doped, Sr-doped, and Ba-doped systems using first-principles calculations. The results showed that doping with Ca made the lowest and next-lowest conduction bands approach each other, which is advantageous for enhancing thermoelectric properties. Thermoelectric calculations showed that the distribution of Ca atoms would have a crucial effect on thermoelectric properties. Although Ca doping did not improve the n-type power factor for any structures examined in the present study, the Seebeck coefficient increased for the p-type, especially for a certain structure at 300 and 600 K, resulting in an improved power factor.

Published
2022

23. Activation mechanism of ruthenium etching by Cl-based radicals in O2/Cl2 plasma

Author

Masaya Imai, Miyako Matsui, Ryoko Sugano, Takashi Shiota, Ko-ichi Takasaki, Makoto Miura, Yohei Ishii, and Kenichi Kuwahara

Subjects
General Engineering, General Physics and Astronomy
Abstract

The Ru etching mechanism was investigated using O2/Cl2 plasma with O, ClO, and Cl radicals. The etch rate drastically increased with a 10%–20% addition of Cl2 to O2 and was lower when using pure O2 or Cl2-rich gas in an ECR etcher. Experimental results indicate that chemical reactions involving Cl-based radicals contributed to the etching reactions. The chemical role of the Cl-based radicals was investigated by density functional theory simulations. The hypothesis tested was that O, ClO, and Cl adsorb on the RuO2 surface when it is irradiated with O-rich plasma. The reactivities of the topmost Ru atoms, where O, ClO, and Cl adsorbed, were compared in terms of the d-band structures. The ClO and Cl were found to enhance the reactivity of the Ru atoms more than O. These findings suggest that Cl-based radicals activate surface Ru atoms, resulting in the formation of volatile RuO4 or RuCl x O y .

Published
2023

24. Reflectivity of Venus's Dayside Disk During the 2020 Observation Campaign: Outcomes and Future Perspectives

Author

Ministerio de Ciencia e Innovación (España), European Commission, Lee, Yeon Joo, Muñoz, Antonio García, Yamazaki, Atsushi, Quémerais, Eric, Mottola, Stefano, Hellmich, Stephan, Granzer, Thomas, Bergond, Gilles, Roth, Martin, Gallego Cano, Eulalia, Chaufray, Jean-Yves, Robidel, Rozenn, Murakami, Go, Masunaga, Kei s, Kaplan, Murat, Erece, Orhan, Hueso, Ricardo, Kabáth, Petr, Špoková, Magdaléna, Sánchez-Lavega, Agustín, Kim, Myung-Jin, Mangano, Valeria, Jessup, Kandis-Lea, Widemann, Thomas, Sugiyama, Ko-ichiro, Watanabe, Shigeto, Yamada, Manabu, Satoh, Takehiko, Nakamura, Masato, Imai, Masataka se, Cabrera, Juan, Ministerio de Ciencia e Innovación (España), European Commission, Lee, Yeon Joo, Muñoz, Antonio García, Yamazaki, Atsushi, Quémerais, Eric, Mottola, Stefano, Hellmich, Stephan, Granzer, Thomas, Bergond, Gilles, Roth, Martin, Gallego Cano, Eulalia, Chaufray, Jean-Yves, Robidel, Rozenn, Murakami, Go, Masunaga, Kei s, Kaplan, Murat, Erece, Orhan, Hueso, Ricardo, Kabáth, Petr, Špoková, Magdaléna, Sánchez-Lavega, Agustín, Kim, Myung-Jin, Mangano, Valeria, Jessup, Kandis-Lea, Widemann, Thomas, Sugiyama, Ko-ichiro, Watanabe, Shigeto, Yamada, Manabu, Satoh, Takehiko, Nakamura, Masato, Imai, Masataka se, and Cabrera, Juan

Abstract

We performed a unique Venus observation campaign to measure the disk brightness of Venus over a broad range of wavelengths in 2020 August and September. The primary goal of the campaign was to investigate the absorption properties of the unknown absorber in the clouds. The secondary goal was to extract a disk mean SO2 gas abundance, whose absorption spectral feature is entangled with that of the unknown absorber at ultraviolet wavelengths. A total of three spacecraft and six ground-based telescopes participated in this campaign, covering the 52–1700 nm wavelength range. After careful evaluation of the observational data, we focused on the data sets acquired by four facilities. We accomplished our primary goal by analyzing the reflectivity spectrum of the Venus disk over the 283–800 nm wavelengths. Considerable absorption is present in the 350–450 nm range, for which we retrieved the corresponding optical depth of the unknown absorber. The result shows the consistent wavelength dependence of the relative optical depth with that at low latitudes, during the Venus flyby by MESSENGER in 2007, which was expected because the overall disk reflectivity is dominated by low latitudes. Last, we summarize the experience that we obtained during this first campaign, which should enable us to accomplish our second goal in future campaigns. © 2022. The Author(s). Published by the American Astronomical Society.

Published
2022

25. Chemical and physical characterization of the isolated protostellar source CB68: FAUST IV

Author

Japan Science and Technology Agency, European Research Council, European Commission, Agencia Estatal de Investigación (España), National Science Foundation (US), Ministerio de Ciencia, Innovación y Universidades (España), Ministry of Education, Culture, Sports, Science and Technology (Japan), Imai, H., Busquet, Gemma, Yamamoto, Satoshi, Japan Science and Technology Agency, European Research Council, European Commission, Agencia Estatal de Investigación (España), National Science Foundation (US), Ministerio de Ciencia, Innovación y Universidades (España), Ministry of Education, Culture, Sports, Science and Technology (Japan), Imai, H., Busquet, Gemma, and Yamamoto, Satoshi

Abstract

The chemical diversity of low-mass protostellar sources has so far been recognized, and environmental effects are invoked as its origin. In this context, observations of isolated protostellar sources without the influence of nearby objects are of particular importance. Here, we report the chemical and physical structures of the low-mass Class 0 protostellar source IRAS 16544−1604 in the Bok globule CB 68, based on 1.3 mm Atacama Large Millimeter/submillimeter Array observations at a spatial resolution of ∼70 au that were conducted as part of the large program FAUST. Three interstellar saturated complex organic molecules (iCOMs), CH3OH, HCOOCH3, and CH3OCH3, are detected toward the protostar. The rotation temperature and the emitting region size for CH3OH are derived to be 131 ± 11 K and ∼10 au, respectively. The detection of iCOMs in close proximity to the protostar indicates that CB 68 harbors a hot corino. The kinematic structure of the C18O, CH3OH, and OCS lines is explained by an infalling–rotating envelope model, and the protostellar mass and the radius of the centrifugal barrier are estimated to be 0.08–0.30 M⊙ and <30 au, respectively. The small radius of the centrifugal barrier seems to be related to the small emitting region of iCOMs. In addition, we detect emission lines of c-C3H2 and CCH associated with the protostar, revealing a warm carbon-chain chemistry on a 1000 au scale. We therefore find that the chemical structure of CB 68 is described by a hybrid chemistry. The molecular abundances are discussed in comparison with those in other hot corino sources and reported chemical models.

Published
2022

26. Discovery of SiO Masers in the 'Water Fountain' Source IRAS 16552−3050

Author

European Commission, Ministerio de Ciencia e Innovación (España), Amada, K., Imai, H., Hamae, Y., Nakashima, K., Shum, K. Y., Tafoya, D., Uscanga, L., Gómez Rivero, José Francisco, Orosz, G., Burns, R. A., European Commission, Ministerio de Ciencia e Innovación (España), Amada, K., Imai, H., Hamae, Y., Nakashima, K., Shum, K. Y., Tafoya, D., Uscanga, L., Gómez Rivero, José Francisco, Orosz, G., and Burns, R. A.

Abstract

In this paper, we report new detections of SiO v = 1 and v = 2 J = 1 → 0 masers in the "water fountain" source IRAS 16552−3050, which was observed with the Nobeyama 45 m telescope during 2021 March–April. Water fountains are evolved stars whose H2O maser spectra trace high-velocity outflows of >100 km s−1. This is the second known case of SiO masers in a water fountain, after their prototypical source, W 43A. These SiO masers should shed light on the evolutionary status of this category of evolved stars, which are likely to be at the end of the asymptotic giant branch phase, when the star exhibits the most copious stellar mass loss, followed by development of the complicated morphologies of planetary nebulae. The origin of a large (up to 25 km s−1) velocity offset of the SiO masers with respect to the systemic velocity derived from the spectrum of CO J = 2 → 1 line is discussed here. © 2022. The American Astronomical Society. All rights reserved.

Published
2022

27. Evolution of the Outflow in the Water Fountain Source IRAS 18043–2116.

Author

Uscanga, L., Imai, H., Gómez, J. F., Tafoya, D., Orosz, G., McCarthy, T. P., Hamae, Y., and Amada, K.

Subjects
*FOUNTAINS, *ASYMPTOTIC giant branch stars, *PLANETARY nebulae, *MASERS
Abstract

We present the spectral and spatial evolution of H2O masers associated with the water fountain source IRAS 18043−2116, found in observations with the Nobeyama 45 m Telescope and the Australia Telescope Compact Array. We have found new highest-velocity components of the H2O masers (at the redshifted side V LSR ≃ 376 km s−1 and at the blueshifted side V LSR ≃ −165 km s−1), and the resulting velocity spread of ≃540 km s−1 breaks the speed record of fast jets/outflows in this type of sources. The locations of those components have offsets from the axis joining the two major maser clusters, indicating a large opening angle of the outflow (∼60°). The evolution of the maser cluster separation of ∼2.9 mas yr−1 and the compact (∼0.″2) CO emission source mapped with the Atacama Large Millimeter-submillimeter Array suggest a very short (∼30 yr) timescale of the outflow. We also confirmed an increase in the flux density of the 22 GHz continuum source. The properties of the jet and the continuum sources and their possible evolution in the transition to the planetary nebula phase are further discussed. [ABSTRACT FROM AUTHOR]

Published
2023
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28. Thermal expansion coefficient and bulk modulus of silicides.

Author

Imai, Motoharu and Hiroto, Takanobu

Abstract

The volumetric thermal expansion coefficient α V is discussed in relation to the bulk modulus B 0 for transition-metal disilicides (TrSi2), alkaline-Earth metal disilicides (AeSi2), Mg2Si, and Si clathrates. For this purpose, the α V of CoSi2 at 300 K is determined to be 3.1 × 10−5 K−1 using powder X-ray diffraction measurements at temperatures ranging from 300 to 835 K. AeSi2 and Mg2Si have B 0 values ranging from 27.9 to 52.9 GPa, while the values for α V range from 3.2 × 10−5 to 4.8 × 10−5 K−1. TrSi2 including CoSi2 has larger B 0 values ranging from 148.9 to 243 GPa and smaller α V values ranging from 2.3 × 10−5 to 3.3 × 10−5 K−1 than AeSi2. Si clathrates have intermediate values of α V and B 0, which are in between those of TrSi2 and AeSi2. Thus, the silicides with small B 0 values tend to have large α V values. [ABSTRACT FROM AUTHOR]

Published
2023
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34. Visualization of local strain in 4H-SiC trench metal-oxide-semiconductor field-effect transistor using synchrotron nanobeam X-ray diffraction

Author

Takeuchi, Wakana, primary, Kagoshima, Eiji, additional, Sumitani, Kazushi, additional, Imai, Yasuhiko, additional, Shibayama, Shigehisa, additional, Sakashita, Mitsuo, additional, Kimura, Shigeru, additional, Tomita, Hidemoto, additional, Nishiwaki, Tsuyoshi, additional, Fujiwara, Hirokazu, additional, and Nakatsuka, Osamu, additional

Published
2022
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37. Preliminary system for data assimilation to infer material parameters from directional solidification experiments: twin experimental study using phase-field method

Author

Y Imai, S Sakane, M Ohno, H Yasuda, and T Takaki

Subjects
General Medicine
Abstract

The integration of phase-field (PF) simulations and in situ observations is a promising approach for understanding dendrite growth. In this study, a preliminary data assimilation system is developed to integrate PF simulations and in situ real-time X-ray radiography during the directional solidification of a binary alloy. In this system, only the region around the tip of a primary arm is used for data assimilation. The validity of the developed system is confirmed through twin experiments for columnar dendrite growth with different inclined angles of preferred growth direction.

Published
2023

40. Completion of JT-60SA construction and contribution to ITER

Author

Kamada Y., Di Pietro E., Hanada M., Barabaschi P., Ide S., Davis S., Yoshida M., Giruzzi G., Sozzi C., Abdel Maksoud W., Abe H., Aiba N., Akiyama T., Ayllon-Guerola J., Arai T., Artaud J. -F., Asakura N., Ashikawa N., Balbinot L., Bando T., Baulaigue O., Belonohy E., Bin W., Bombarda F., Bolzonella T., Bonne F., Bonotto M., Botija J., Cabrera-Perez S., Cardella A., Carraro L., Cavalier J., Chernyshova M., Chiba S., Clement-Lorenzo S., Cocilovo V., Coda S., Coelho R., Coffey I., Collin B., Corato V., Cucchiaro A., Czarski T., Dairaku M., Day C., de la Luna E., De Tommasi G., Decool P., Di Pace L., Dibon M., Disset G., Ejiri A., Endo Y., Ezumi N., Falchetto G., Fassina A., Fejoz P., Ferro A., Fietz W., Figini L., Fornal T., Frello G., Fujita T., Fukuda T., Fukui K., Fukumoto M., Furukawa M., Futatani S., Gabellieri L., Gaio E., Galazka K., Garcia J., Garcia-Dominguez J., Garcia-Lopez J., Garcia-Munoz M., Garzotti L., Gasparini F., Gharafi S., Giacomelli L., Ginoulhiac G., Giudicotti L., Guillen Gonzalez R., Hajnal N., Hall S., Hamada K., Hanada K., Hasegawa K., Hatae T., Hatakeyama S., Hauer V., Hayashi N., Hayashi T., Heller R., Higashijima S., Hinata J., Hiranai S., Hiratsuka J., Hiwatari R., Hoa C., Homma H., Honda A., Honda M., Horiike H., Hoshino K., Hurzlmeier H., Iafrati M., Ibano K., Ichige H., Ichikawa M., Ichimura M., Ida K., Idei H., Iijima T., Iio S., Ikeda R., Ikeda Y., Imai T., Imazawa R., Inagaki S., Inomoto M., Inoue S., Isayama A., Ishida S., Ishii Y., Isobe M., Janky F., Joffrin E., Jokinen A., Kado S., Kajita S., Kajiwara K., Kamata I., Kaminaga A., Kamiya K., Kanapienyte D., Kashiwa Y., Kashiwagi M., Katayama K., Kawamata Y., Kawamura G., Kawano K., Kawashima H., Kin F., Kitajima S., Kiyono K., Kizu K., Kobayashi K., Kobayashi M., Kobayashi S., Kobayashi T., Kocsis G., Koide Yo., Koide Yu., Kojima A., Kokusen S., Komuro K., Konishi S., Kovacsik A., Ksiazek I., Kubkowska M., Kuhner G., Kuramochi M., Kurihara K., Kurki-Suonio T., Kurniawan A. B., Kuwata T., Lacroix B., Lamaison V., Lampasi A., Lang P., Lauber P., Lawson K., Louzguiti A., Maekawa R., Maekawa T., Maeyama S., Maffia G., Maget P., Mailloux J., Maione I., Maistrello A., Malinowski K., Marchiori G., Marechal J. -L., Massaut V., Masuzaki S., Matsunaga G., Matsunaga S., Mayri Ch., Mattei M., Medrano M., Mele A., Meyer I., Michel F., Minami T., Miyata Y., Miyazawa J., Miyo Y., Mizuuchi T., Mogaki K., Morales J., Moreau P., Mori M., Morisaki T., Morishima S., Moriyama S., Moro A., Murakami H., Murayama M., Murakami S., Nagasaki K., Naito O., Nakamura S., Nakano T., Nakashima Y., Nardino V., Narita E., Narushima Y., Natsume K., Nemoto S., Neu R., Nicollet S., Nishikawa M., Nishimura S., Nishiura M., Nishiyama T., Nocente M., Nobuta Y., Novello L., Nunio F., Ochoa S., Ogawa T., Ogawa Y., Ohdachi S., Ohmori Y., Ohno N., Ohtani Y., Ohzeki M., Oishi T., Okano F., Okano J., Okano K., Onishi Y., Osakabe M., Oshima T., Ostuni V., Oya M., Oya Y., Oyama N., Ozeki T., Pasqualotto R., Pelli S., Peretti E., Phillips G., Piccinni C., Pigatto L., Pironti A., Pizzuto A., Plockl B., Polli G., Poncet J. -M., Ponsot P., Puiatti M., Radloff D., Raimondi V., Ramos F., Rancsik P., Ricci D., Ricciarini S., Rincon E., Romano A., Rossi P., Roussel P., Rubino G., Saeki H., Sagara A., Sakakibara S., Sakamoto H., Sakamoto M., Sakamoto Y., Sakasai A., Sakata S., Sakuma T., Sakurai S., Salanon B., Salmi A., Sannazzaro G., Sano R., Sanpei A., Sasajima T., Sasaki S., Sasao H., Sato F., Sato M., Sawahata M., Scherber A., Scully S., Seki M., Seki S., Shibama Y., Shibata Y., Shikama T., Shimada K., Shimono M., Shinde J., Shinya T., Shinohara K., Shirai H., Shiraishi J., Soare S., Soleto A., Someya Y., Streciwilk-Kowalska E., Strobel H., Sueoka M., Sukegawa A., Sulistyanintyas D., Sumida S., Sunaoshi H., Suzuki H., Suzuki M., Suzuki S., Suzuki T., Suzuki Y., Svoboda J., Szabolics T., Szepesi T., Takahashi K., Takase Y., Takechi M., Takeda K., Takeiri Y., Takenaga H., Taliercio C., Tamura N., Tanaka H., Tanaka K., Tani K., Tanigawa H., Tardocchi M., Terakado A., Terakado M., Terakado T., Teuchner B., Tilia B., Tobita K., Toi K., Toida N., Tojo H., Tokitani M., Tokuzawa T., Tormarchio V., Tomine M., Torre A., Totsuka T., Tsuchiya K., Tsujii N., Tsuru D., Tsutsui H., Uchida M., Ueda Y., Uno J., Urano H., Usui K., Utoh H., Valisa M., Vallar M., Vallcorba-Carbonell R., Vallet J. -C., Varela J., Vega J., Verrecchia M., Vieillard L., Villone F., Vincenzi P., Wada K., Wada R., Wakatsuki T., Wanner M., Watanabe F., Watanabe K., Wauters T., Wiesen S., Wischmeier M., Yagi M., Yagyu J., Yajima M., Yokooka S., Yokoyama M., Yamamoto S., Yamanaka H., Yamauchi K., Yamauchi Y., Yamazaki H., Yamazaki K., Yamazaki R., Yamoto S., Yanagi S., Yanagihara K., Yoshizawa N., Zani L., Zito P., Kamada, Y., Di Pietro, E., Hanada, M., Barabaschi, P., Ide, S., Davis, S., Yoshida, M., Giruzzi, G., Sozzi, C., Abdel Maksoud, W., Abe, H., Aiba, N., Akiyama, T., Ayllon-Guerola, J., Arai, T., Artaud, J. -F., Asakura, N., Ashikawa, N., Balbinot, L., Bando, T., Baulaigue, O., Belonohy, E., Bin, W., Bombarda, F., Bolzonella, T., Bonne, F., Bonotto, M., Botija, J., Cabrera-Perez, S., Cardella, A., Carraro, L., Cavalier, J., Chernyshova, M., Chiba, S., Clement-Lorenzo, S., Cocilovo, V., Coda, S., Coelho, R., Coffey, I., Collin, B., Corato, V., Cucchiaro, A., Czarski, T., Dairaku, M., Day, C., de la Luna, E., De Tommasi, G., Decool, P., Di Pace, L., Dibon, M., Disset, G., Ejiri, A., Endo, Y., Ezumi, N., Falchetto, G., Fassina, A., Fejoz, P., Ferro, A., Fietz, W., Figini, L., Fornal, T., Frello, G., Fujita, T., Fukuda, T., Fukui, K., Fukumoto, M., Furukawa, M., Futatani, S., Gabellieri, L., Gaio, E., Galazka, K., Garcia, J., Garcia-Dominguez, J., Garcia-Lopez, J., Garcia-Munoz, M., Garzotti, L., Gasparini, F., Gharafi, S., Giacomelli, L., Ginoulhiac, G., Giudicotti, L., Guillen Gonzalez, R., Hajnal, N., Hall, S., Hamada, K., Hanada, K., Hasegawa, K., Hatae, T., Hatakeyama, S., Hauer, V., Hayashi, N., Hayashi, T., Heller, R., Higashijima, S., Hinata, J., Hiranai, S., Hiratsuka, J., Hiwatari, R., Hoa, C., Homma, H., Honda, A., Honda, M., Horiike, H., Hoshino, K., Hurzlmeier, H., Iafrati, M., Ibano, K., Ichige, H., Ichikawa, M., Ichimura, M., Ida, K., Idei, H., Iijima, T., Iio, S., Ikeda, R., Ikeda, Y., Imai, T., Imazawa, R., Inagaki, S., Inomoto, M., Inoue, S., Isayama, A., Ishida, S., Ishii, Y., Isobe, M., Janky, F., Joffrin, E., Jokinen, A., Kado, S., Kajita, S., Kajiwara, K., Kamata, I., Kaminaga, A., Kamiya, K., Kanapienyte, D., Kashiwa, Y., Kashiwagi, M., Katayama, K., Kawamata, Y., Kawamura, G., Kawano, K., Kawashima, H., Kin, F., Kitajima, S., Kiyono, K., Kizu, K., Kobayashi, K., Kobayashi, M., Kobayashi, S., Kobayashi, T., Kocsis, G., Koide, Yo., Koide, Yu., Kojima, A., Kokusen, S., Komuro, K., Konishi, S., Kovacsik, A., Ksiazek, I., Kubkowska, M., Kuhner, G., Kuramochi, M., Kurihara, K., Kurki-Suonio, T., Kurniawan, A. B., Kuwata, T., Lacroix, B., Lamaison, V., Lampasi, A., Lang, P., Lauber, P., Lawson, K., Louzguiti, A., Maekawa, R., Maekawa, T., Maeyama, S., Maffia, G., Maget, P., Mailloux, J., Maione, I., Maistrello, A., Malinowski, K., Marchiori, G., Marechal, J. -L., Massaut, V., Masuzaki, S., Matsunaga, G., Matsunaga, S., Mayri, Ch., Mattei, M., Medrano, M., Mele, A., Meyer, I., Michel, F., Minami, T., Miyata, Y., Miyazawa, J., Miyo, Y., Mizuuchi, T., Mogaki, K., Morales, J., Moreau, P., Mori, M., Morisaki, T., Morishima, S., Moriyama, S., Moro, A., Murakami, H., Murayama, M., Murakami, S., Nagasaki, K., Naito, O., Nakamura, S., Nakano, T., Nakashima, Y., Nardino, V., Narita, E., Narushima, Y., Natsume, K., Nemoto, S., Neu, R., Nicollet, S., Nishikawa, M., Nishimura, S., Nishiura, M., Nishiyama, T., Nocente, M., Nobuta, Y., Novello, L., Nunio, F., Ochoa, S., Ogawa, T., Ogawa, Y., Ohdachi, S., Ohmori, Y., Ohno, N., Ohtani, Y., Ohzeki, M., Oishi, T., Okano, F., Okano, J., Okano, K., Onishi, Y., Osakabe, M., Oshima, T., Ostuni, V., Oya, M., Oya, Y., Oyama, N., Ozeki, T., Pasqualotto, R., Pelli, S., Peretti, E., Phillips, G., Piccinni, C., Pigatto, L., Pironti, A., Pizzuto, A., Plockl, B., Polli, G., Poncet, J. -M., Ponsot, P., Puiatti, M., Radloff, D., Raimondi, V., Ramos, F., Rancsik, P., Ricci, D., Ricciarini, S., Rincon, E., Romano, A., Rossi, P., Roussel, P., Rubino, G., Saeki, H., Sagara, A., Sakakibara, S., Sakamoto, H., Sakamoto, M., Sakamoto, Y., Sakasai, A., Sakata, S., Sakuma, T., Sakurai, S., Salanon, B., Salmi, A., Sannazzaro, G., Sano, R., Sanpei, A., Sasajima, T., Sasaki, S., Sasao, H., Sato, F., Sato, M., Sawahata, M., Scherber, A., Scully, S., Seki, M., Seki, S., Shibama, Y., Shibata, Y., Shikama, T., Shimada, K., Shimono, M., Shinde, J., Shinya, T., Shinohara, K., Shirai, H., Shiraishi, J., Soare, S., Soleto, A., Someya, Y., Streciwilk-Kowalska, E., Strobel, H., Sueoka, M., Sukegawa, A., Sulistyanintyas, D., Sumida, S., Sunaoshi, H., Suzuki, H., Suzuki, M., Suzuki, S., Suzuki, T., Suzuki, Y., Svoboda, J., Szabolics, T., Szepesi, T., Takahashi, K., Takase, Y., Takechi, M., Takeda, K., Takeiri, Y., Takenaga, H., Taliercio, C., Tamura, N., Tanaka, H., Tanaka, K., Tani, K., Tanigawa, H., Tardocchi, M., Terakado, A., Terakado, M., Terakado, T., Teuchner, B., Tilia, B., Tobita, K., Toi, K., Toida, N., Tojo, H., Tokitani, M., Tokuzawa, T., Tormarchio, V., Tomine, M., Torre, A., Totsuka, T., Tsuchiya, K., Tsujii, N., Tsuru, D., Tsutsui, H., Uchida, M., Ueda, Y., Uno, J., Urano, H., Usui, K., Utoh, H., Valisa, M., Vallar, M., Vallcorba-Carbonell, R., Vallet, J. -C., Varela, J., Vega, J., Verrecchia, M., Vieillard, L., Villone, F., Vincenzi, P., Wada, K., Wada, R., Wakatsuki, T., Wanner, M., Watanabe, F., Watanabe, K., Wauters, T., Wiesen, S., Wischmeier, M., Yagi, M., Yagyu, J., Yajima, M., Yokooka, S., Yokoyama, M., Yamamoto, S., Yamanaka, H., Yamauchi, K., Yamauchi, Y., Yamazaki, H., Yamazaki, K., Yamazaki, R., Yamoto, S., Yanagi, S., Yanagihara, K., Yoshizawa, N., Zani, L., and Zito, P.

Subjects
assembly, Cryostat, Nuclear and High Energy Physics, Materials science, Tokamak, Nuclear engineering, Plasma, Condensed Matter Physics, Field coil, ITER risk mitigation, Overcurrent, law.invention, Control theory, law, Electromagnetic coil, research plan, broader approach, Voltage
Abstract

Construction of the JT-60SA tokamak was completed on schedule in March 2020. Manufacture and assembly of all the main tokamak components satisfied technical requirements, including dimensional accuracy and functional performances. Development of the plasma heating systems and diagnostics have also progressed, including the demonstration of the favourable electron cyclotron range of frequency (ECRF) transmission at multiple frequencies and the achievement of long sustainment of a high-energy intense negative ion beam. Development of all the tokamak operation control systems has been completed, together with an improved plasma equilibrium control scheme suitable for superconducting tokamaks including ITER. For preparation of the tokamak operation, plasma discharge scenarios have been established using this advanced equilibrium controller. Individual commissioning of the cryogenic system and the power supply system confirmed that these systems satisfy design requirements including operational schemes contributing directly to ITER, such as active control of heat load fluctuation of the cryoplant, which is essential for dynamic operation in superconducting tokamaks. The integrated commissioning (IC) is started by vacuum pumping of the vacuum vessel and cryostat, and then moved to cool-down of the tokamak and coil excitation tests. Transition to the super-conducting state was confirmed for all the TF, EF and CS coils. The TF coil current successfully reached 25.7 kA, which is the nominal operating current of the TF coil. For this nominal toroidal field of 2.25 T, ECRF was applied and an ECRF plasma was created. The IC was, however, suspended by an incident of over current of one of the superconducting equilibrium field coil and He leakage caused by insufficient voltage holding capability at a terminal joint of the coil. The unique importance of JT-60SA for H-mode and high-β steady-state plasma research has been confirmed using advanced integrated modellings. These experiences of assembly, IC and plasma operation of JT-60SA contribute to ITER risk mitigation and efficient implementation of ITER operation.

Published
2022

46. Thermal expansion coefficient and bulk modulus of silicides

Author

Motoharu Imai and Takanobu Hiroto

Subjects
General Engineering, General Physics and Astronomy
Abstract

The volumetric thermal expansion coefficient α V is discussed in relation to the bulk modulus B 0 for transition-metal disilicides (TrSi2), alkaline-Earth metal disilicides (AeSi2), Mg2Si, and Si clathrates. For this purpose, the α V of CoSi2 at 300 K is determined to be 3.1 × 10−5 K−1 using powder X-ray diffraction measurements at temperatures ranging from 300 to 835 K. AeSi2 and Mg2Si have B 0 values ranging from 27.9 to 52.9 GPa, while the values for α V range from 3.2 × 10−5 to 4.8 × 10−5 K−1. TrSi2 including CoSi2 has larger B 0 values ranging from 148.9 to 243 GPa and smaller α V values ranging from 2.3 × 10−5 to 3.3 × 10−5 K−1 than AeSi2. Si clathrates have intermediate values of α V and B 0, which are in between those of TrSi2 and AeSi2. Thus, the silicides with small B 0 values tend to have large α V values.

Published
2022

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