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ionsShiina, Yoko*; Kinoshita, Ryo*; Funada, Shuhei*; Matsuda, Makoto; Imai, Makoto*; Kawatsura, Kiyoshi*; Sataka, Masao*; Sasa, Kimikazu*; Kaneko, Toshiaki*; Tomita, Shigeo*
Physical Review A, 110(6), p.062826_1 - 062826_7, 2024/12
Times Cited Count：0 Percentile：0.00(Optics)Kaneko, Fumitoshi*; Kawaguchi, Tatsuya*; Radulescu, A.*; Iwase, Hiroki*; Morikawa, Toshiaki*; Takata, Shinichi; Nishiura, Masayoshi*; Hou, Z.*
Review of Scientific Instruments, 90(9), p.093906_1 - 093906_6, 2019/09
Times Cited Count：5 Percentile：25.30(Instruments & Instrumentation)Okamoto, Yoshihiro; Nagai, Takayuki; Kaneko, Koji; Motokawa, Ryuhei; Haga, Yoshinori; Yamanaka, Keisuke*; Ota, Toshiaki*
2017-Nendo Seika Kokaigata Riyo Seika Hokokusho (Ritsumeikan Daigaku SR Senta), p.33 - 36, 2018/00
The high-level radioactive waste solution which generated from a spent nuclear fuel reprocessing process are mixed with a borosilicate glass frit in a vitrification process, and a chemical stable glass solidified body is produced. To understand local structure of light elements included in a glass solidified body, we carried out a B K-edge XANES measurement of raw glass frits and simulated radioactive waste glasses. As a result of this estimation of boron local structure in glass samples, it was found that the sp
type boron (BO
) percentage increases and the sp
type (BO
) percentage by increasing the sodium content in glass frits.
Chiba, Atsuya; Saito, Yuichi; Narumi, Kazumasa; Yamada, Keisuke; Kaneko, Toshiaki*
Nuclear Instruments and Methods in Physics Research B, 315, p.81 - 84, 2013/11
Times Cited Count：1 Percentile：11.10(Instruments & Instrumentation)The average charge of the constituent ions resulting from foil-induced dissociation of cluster ion is smaller than that of the single ion passing through the foil at same speed. This charge reduction effect is one of the most important phenomena for understanding the interaction of cluster ions with electrons in a solid, and the theories suggested that it strongly depends on the internuclear distance of the constituent ions. However, the relationship between the internuclear distance and the charge state has still not been shown quantitatively. We developed a method to evaluate the relationship by analyzing the divergence angle of the constituent ions after foil penetration using Coulomb explosion imaging technique. As a result for 6-MeV C
, it was shown quantitatively that the charge reduction effect decreases with increasing the internuclear distance of the constituent ion in the solid.
Kaneko, Toshiaki*; Ihara, Kosuke*; Kono, Maasa*; Saito, Yuichi; Chiba, Atsuya; Narumi, Kazumasa
JAEA-Review 2012-046, JAEA Takasaki Annual Report 2011, P. 164, 2013/01
ion moving in a solidChiba, Atsuya; Saito, Yuichi; Narumi, Kazumasa; Yamada, Keisuke; Kaneko, Toshiaki*
JAEA-Review 2012-046, JAEA Takasaki Annual Report 2011, P. 161, 2013/01
An average charge of the constituent ions resulting from the foil-induced dissociation of cluster ions is smaller than that of monatomic ions at the same speed. It is considered that such a charge reduction effect in cluster ion bombardments depend strongly on the internuclear distance between constituent ions moving in a solid. However, there are few reports in which average charges of the constituent ions had been quantitatively evaluated in terms of their internuclear distance increasing by the screened Coulomb repulsion. Therefore, we developed a method which evaluate quantitatively the average charge for internuclear distance of constituent ions in solid through the measurements of the divergence angle of the constituent ions after foil penetration. The achieved results are approximately equal to the theoretical value derived from model considering the cluster effect in average charge.
Chiba, Atsuya; Saito, Yuichi; Narumi, Kazumasa; Yamada, Keisuke; Kaneko, Toshiaki*
Dai-25-Kai Tandemu Kasokuki Oyobi Sono Shuhen Gijutsu No Kenkyukai Hokokushu, p.98 - 101, 2012/07
Availability of the swift cluster ion is expected as new irradiation source, because the cluster ion bombardment to the solid brings irradiation effects different from the monatomic ion bombardment at the same speed. This unique effect, cluster effect, is caused via the physical processes that a number of high energy ions within a narrow spatiotemporal region make the high density excited states and that the constituent ion influences with respect to one another. For understanding of the expression mechanism of cluster effect, detailed investigation of these two physical processes are needed. In this study, with a focus on the interaction between constituent ions, we developed an analyzing method that shows quantitatively the relationship between the internuclear distance of constituent ions and their charge states, using the Coulomb explosion imaging technique, to investigate the contribution of the screened Coulomb potential to the cluster effect.
ionsChiba, Atsuya; Saito, Yuichi; Narumi, Kazumasa; Yamada, Keisuke; Kaneko, Toshiaki*
JAEA-Review 2011-043, JAEA Takasaki Annual Report 2010, P. 151, 2012/01
In order to understand the mechanism of charge reduction in cluster ions observed in the foil-transmission experiments, we investigate contributions to charge states of the cluster constituent ions from ion-induced potential. For the C ions passing through a this foil, we found out that the charge states of tracing ions are larger than that of leading ions.
Kaneko, Toshiaki*; Saito, Yuichi; Chiba, Atsuya; Narumi, Kazumasa
JAEA-Review 2011-043, JAEA Takasaki Annual Report 2010, P. 153, 2012/01
ion passing through a thin foilChiba, Atsuya; Saito, Yuichi; Narumi, Kazumasa; Yamada, Keisuke; Kaneko, Toshiaki*
Dai-24-Kai Tandemu Kasokuki Oyobi Sono Shuhen Gijutsu No Kenkyukai Hokokushu, p.121 - 124, 2011/07
The average charge states of swift cluster ions passed through a thin foil are smaller than that of the single ions at the same speed. It is considered that such a phenomenon is derived from the mutual screened Coulomb interactions among the cluster constituent ions and the collective excitations of the target electrons induced by the constituent ions. In order to evaluate the contribution to the charge states from the fields of the collective excitations formed at the backward of the moving ion, using the C ions, the charge states measurements were performed taking into account the relative position (leading and trailing) of the constituent ions. The experimental results showed that the charge states of the trailing ions are larger than that of the leading ions, and that this tendency becomes strong with increasing the product of charges.
constituents passing through a thin carbon foilChiba, Atsuya; Saito, Yuichi; Narumi, Kazumasa; Takahashi, Yasuyuki; Yamada, Keisuke; Kaneko, Toshiaki*
Nuclear Instruments and Methods in Physics Research B, 269(9), p.824 - 828, 2011/05
Times Cited Count：3 Percentile：25.97(Instruments & Instrumentation)It is necessary to clarify the relationship between the internuclear distance of the cluster constituent ions and these charge states for the elucidation of mechanism of the vicinage effects which are expressed due to the interaction with matter. Therefore the coincidence measurement between divergence angles and final charge states of the constituent ions resulting from dissociation of 6-MeV C ions in a thin carbon foil were performed. The strong dependence of the final charge state of constituent ions on the initial internuclear distance of projectile ion was quantitatively indicated by the fitting analysis of the angular distributions for various final charge-state combinations using the Monte Carlo particle trajectory simulation.
ionsChiba, Atsuya; Saito, Yuichi; Narumi, Kazumasa; Takahashi, Yasuyuki; Yamada, Keisuke; Kaneko, Toshiaki*
JAEA-Review 2010-065, JAEA Takasaki Annual Report 2009, P. 163, 2011/01
The evaluation of the charge state and charge exchange process of the cluster constituent ions inside solid is extremely important for the clarification of the vicinage effect, because the essential interaction forces such as stopping power, wake force and Coulomb repulsion is strongly correlated to the charge state of individual constituent ions. Therefore, the measurement of the divergence angular distributions classified into the charge-state combination of constituent ions resulting from foil-induced dissociation of 6-MeV C ions was carried out in order to investigate the relationship between the internuclear distance and the charge state of individual constituent ions. We suggests that the final charge-state combination of constituents emerging from the foil depends on the initial internuclear-distance which is fluctuated due to a vibration excitation of C ion.
Chiba, Atsuya; Saito, Yuichi; Narumi, Kazumasa; Adachi, Masahiro; Yamada, Keisuke; Takahashi, Yasuyuki; Kaneko, Toshiaki*
JAEA-Conf 2008-012, p.84 - 86, 2009/03
no abstracts in English
cluster ion structure utilizing coulomb explosion imagingAdachi, Masahiro; Saito, Yuichi; Chiba, Atsuya; Narumi, Kazumasa; Yamada, Keisuke; Kaneko, Toshiaki*
Radiation Physics and Chemistry, 77(10-12), p.1328 - 1332, 2008/10
Times Cited Count：1 Percentile：9.77(Chemistry, Physical)no abstracts in English
cluster ionChiba, Atsuya; Saito, Yuichi; Narumi, Kazumasa; Adachi, Masahiro; Kaneko, Toshiaki*
Physical Review A, 76(6), p.063201_1 - 063201_6, 2007/12
Times Cited Count：13 Percentile：53.70(Optics)The charge states of fragment ions were measured for 1-MeV/atom C cluster ions penetrating a carbon foil of 2.4-
g/cm thickness. Those ions were detected with a luminance plate detector monitored by a CCD camera. The detected ion signals were traced by coulomb explosion imaging technique, which enabled us to classify charge states of each fragment ion and spatial structure of a cluster ion on emerging from the foil. Using this technique, for the first time, we found that (1) the measured average charges of the fragment ions in a triangular structure are smaller than those in a linear-chain structure, and (2) the edge-position ions in a linear structure have the average charges greater than the middle-position ion. These experimental results are well supported by a recent theory on the cluster average charge.
Chiba, Atsuya; Saito, Yuichi; Narumi, Kazumasa; Adachi, Masahiro; Kaneko, Toshiaki*
JAEA-Review 2006-042, JAEA Takasaki Annual Report 2005, P. 176, 2007/02
The charge states were measured for the constituent ions of 1 MeV/atom C ions passing through a carbon thin foil. The constituent ions of C ions deflected by the deflection plates were detected with a luminance plate position detector monitored by a CCD camera. Since the detected ion signals contain the information of charge states and cluster structure, this measurement method enabled us to investigate the structure-dependent of the average charges in the cluster ions. The data clearly show that the measured average charges of C ions in a linear-chain structure are larger than those in a ring structure. Moreover we found that the edge-position ions in a linear structure have the average charges larger than the middle-position ion. These experimental results are well supported by a recent theory on the cluster average charge.
Kudo, Hiroshi*; Iwasaki, Wataru*; Uchiyama, Rumi*; Tomita, Shigeo*; Shima, Kunihiro*; Sasa, Kimikazu*; Ishii, Satoshi*; Narumi, Kazumasa; Naramoto, Hiroshi; Saito, Yuichi; et al.
Japanese Journal of Applied Physics, Part 2, 45(22), p.L565 - L568, 2006/06
Times Cited Count：16 Percentile：50.56(Physics, Applied)The first observation of the energy distribution of electrons emitted from solids bombarded by MeV atom clusters is reported. In the backward direction, using graphite and Si bombarded by C and Al (n 
8), an appreciable suppression of electron emission has been observed at electron energies lower than 
10 eV. Electron yield per atom decreases with increasing n, and becomes less than 50% at n 
3, relative to the case of n = 1. The experimental results cannot be explained in terms of projectile stopping cross sections nor by the clearing-the-way effect. It is probable that the suppressed electron emission is a result of the suppression of the transport or surface transmission of the produced low-energy electrons, rather than of the suppression of ionization.
Nagao, Yoshiharu; Hosoya, Toshiaki; Kaneko, Yoshihiko*
Nihon Genshiryoku Gakkai Wabun Rombunshi, 1(2), p.153 - 163, 2002/06
no abstracts in English
Obara, Kenjiro; Kakudate, Satoshi; Oka, Kiyoshi; Furuya, Kazuyuki; ; Tada, Eisuke; Shibanuma, Kiyoshi; Koizumi, Koichi; Okawa, Yoshinao; Morita, Yosuke; et al.
JAERI-Tech 96-011, 111 Pages, 1996/03
no abstracts in English
Chiba, Atsuya; Saito, Yuichi; Narumi, Kazumasa; Yamada, Keisuke; Kaneko, Toshiaki*
no journal, ,
no abstracts in English
