Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Kabumoto, Hiroshi; Nakagawa, Sohei; Matsuda, Makoto
JAEA-Conf 2022-002, 146 Pages, 2023/03
"The 34th Meeting for Tandem Accelerators and their Associated Technologies" was held on July 21-22, 2022 organized by Nuclear Science Research Institute of the Japan Atomic Energy Agency. This meeting was held only on-line for preventing the spread of COVID-19 infection. The purpose of this meeting is contribution of development for related technology and of management of facilities through exchange of information among the researchers and engineers using and operating electrostatics accelerator facilities like tandem accelerators. There were 25 presentations which contains current status report of facility, technical development of accelerator, research of application. The total number of participants was a hundred, from 26 universities, research organizations and industries. This meeting consisted of only oral session, a poster session was not carried out because of on-line meeting. This proceeding compiles the contents of report papers in the meeting.
Jinno, Satoshi; Fujita, Natsuko; Tanuma, Hajime*
Dai-23-Kai AMS Shimpojiumu Hokokushu, p.89 - 92, 2022/12
The measurement of chlorine-36 (
Cl) in AMS, which is important for the dating of saline groundwater, is more difficult than other nuclides due to the isobaric interference by sulfur-36 (S). In general, acceleration voltages of 6 MV or higher are required to separate Cl and S. Therefore, this study aims to develop an ion funnel reaction cell and incorporate it into the low energy side of JAEA-AMS-TONO-5MV to selectively suppress S.
Honda, Maki
Journal of the Mass Spectrometry Society of Japan, 70(4), p.282 - 283, 2022/12
The development of measurement and chemical separation techniques in the accelerator mass spectrometry (AMS) method has enabled highly sensitive analysis of 
Pu (half-life 8.1
10
years), 
Fe (half-life 2.6210
years), and 
Sr (half-life 28.9 years) in AMS. For example, the study analyzing Pu in ferromanganese crust samples successfully quantified Pu from outside the solar system, which had been hidden by Pu from nuclear tests. Furthermore, the research has revealed that Pu is produced in neutron star mergers, etc., leading to unraveling the production sites where the heavy elements originate. This topic highlights the frontline of studies on Pu, Fe, and Sr utilizing AMS.
Sr and 
Cs by AMSHonda, Maki; Martschini, M.*; Wieser, A.*; Marchhart, O.*; Lachner, J.*; Priller, A.*; Steier, P.*; Golser, R.*; Sakaguchi, Aya*
JAEA-Conf 2022-001, p.85 - 90, 2022/11
Accelerator mass spectrometry (AMS) is an analytical method that combines mass spectrometry with a tandem accelerator, which has been used mainly in nuclear physics experiments. AMS is used to measure radionuclides with half-lives of 10
-10
years. For radionuclides with half-lives of this order, the method of measuring their mass is 10-10 times more sensitive than measuring their activity. Because of this advantage, AMS has been widely applied in Earth and planetary sciences, atomic energy research, and other fields. Among the various studies, Wallner et al. (2021, 2016) have achieved excellent work in Earth and planetary sciences. For example, they have attained the ultra-sensitive analysis of Fe and Pu in environmental samples. These are radionuclides produced by rapid-neutron-capture (r-process) nucleosynthesis. Our recent work shows that a new AMS system (VERA, University of Vienna), which combines laser isobaric separation and a typical AMS system, has been successfully applied to the ultra-sensitive determination of Sr and Cs in environment. For Sr in environmental samples, the 
-ray measurement by the milking of the daughter nuclide Y is still the principal method, which takes 3-6 weeks. The new AMS method has a detection limit of 
0.1 mBq, which is comparable to that of -ray measurement, with a more straightforward chemical treatment than -measurement. Our achievement demonstrates that AMS can be a practical new method for determining Sr in the environment.
Matsubara, Akihiro
Shototsu, 12(4), P. 126, 2015/07
no abstracts in English
I in environmental samples by AMS and NAA using an anion exchange resin diskSuzuki, Takashi; Bamba, Shigeru*; Kitamura, Toshikatsu; Kabuto, Shoji*; Isogai, Keisuke*; Amano, Hikaru
Nuclear Instruments and Methods in Physics Research B, 259(1), p.370 - 373, 2007/06
Times Cited Count：14 Percentile：68.37(Instruments & Instrumentation)no abstracts in English
I by Accelerator Mass Spectrometry (AMS) and its application on earth and environmental sciencesSuzuki, Takashi; Muramatsu, Yasuyuki*
Radioisotopes, 54, p.51 - 53, 2005/00
no abstracts in English
Aramaki, Takafumi
JAERI-Research 99-007, 22 Pages, 1999/02
JAERI-Research-99-007.pdf:1.52MB
no abstracts in English
Ca with RCNP AVF cyclotron*; *; *; *; *; Nagame, Yuichiro
Nuclear Instruments and Methods in Physics Research A, 29, p.151 - 154, 1987/00
no abstracts in English
Matsubara, Akihiro; Fujita, Natsuko; Nishizawa, Akimitsu*; Miyake, Masayasu*
no journal, ,
no abstracts in English
E ionization chamber in the AMS systemMatsubara, Akihiro; Fujita, Natsuko; Nishizawa, Akimitsu*; Miyake, Masayasu*
no journal, ,
no abstracts in English
Jeon, H.; Ogawa, Hiroshi*; Otosaka, Shigeyoshi
no journal, ,
Radiocarbon content of marine dissolved organic carbon (DO
C) can provide useful information on how organic carbon is produced, transported, and ultimately sequestered in the ocean interior. We conducted research to present the first set of full-depth profiles for DOC along a transect from the central South Pacific Ocean to Chukchi Sea. In order to measure radiocarbon contents of seawater samples, they should be processed with a specific preparation system consists of the custom quartz reactor, dedicated vacuum line and UV lamp followed by radiocarbon counting with an accelerator mass spectrometer. As the first step of the study, we have developed the irradiation procedure using a low-pressure Hg lamp and an oxidation catalyst. We present here how the system is progressing as well as what radiocarbon study in the central Pacific Ocean means for better understanding of oceanic carbon cycle.
Matsubara, Akihiro; Fujita, Natsuko; Miyake, Masayasu*; Nishizawa, Akimitsu*
no journal, ,
no abstracts in English
Jeon, H.; Otosaka, Shigeyoshi; Yamashita, Yohei*; Ogawa, Hiroshi*
no journal, ,
The ocean is a huge reservoir of dissolved organic carbon that contains almost the same amount of carbon in the atmosphere. Radiocarbon signatures of dissolved organic carbon (DOC) in seawater can provide useful information on how organic carbon is produced, transported, and ultimately sequestered in the ocean's interior. In order to measure radiocarbon contents of seawater samples, they should be processed with a specific preparation system consists of the custom quartz reactor, dedicated vacuum line and UV lamp followed by radiocarbon counting with an accelerator mass spectrometer. As the first step of the study, we developed the irradiation procedure using a low-pressure Hg lamp and an oxidation catalyst. We present here not only how the system is progressing but also what radiocarbon study in the central Pacific Ocean means for better understanding of oceanic carbon cycle.
Watanabe, Takahiro; Kokubu, Yoko; Fujita, Natsuko; Matsubara, Akihiro*; Nishio, Tomohiro*; Miyake, Masayasu; Kato, Motohisa*; Isozaki, Nobuhiro*; Torazawa, Hitoshi*; Nishizawa, Akimitsu*; et al.
no journal, ,
Radiocarbon dating by Accelerator Mass Spectrometry is widely used for earth and environmental sciences. For high-precision analyses, automatic preparation system and standard methods are needed. The preparation system by elemental analyzer (EA) has been reported. However, we should make clear the changes in background level during the preparation. In this study, we continued radiocarbon dating of international standard materials using the EA at JAEA-AMS-TONO. The radiocarbon concentrations of the standard materials were agreement with the consensus values within 
2 sigma.
Kuwabara, Jun
no journal, ,
The principle and characteristic of Accelerator Mass Spectrometry (AMS) are explained. Dating method in archeology using AMS and the performance of AMS, installed at Ohminato Facility of JAEA, are also explained.
Jeon, H.; Otosaka, Shigeyoshi; Watanabe, Takahiro; Aze, Takahiro*; Miyairi, Yosuke*; Yokoyama, Yusuke*; Ogawa, Hiroshi*
no journal, ,
Measurements of the dissolved organic radio carbon (DOC-14) are expected to broaden our perspective on the role of DOC in the marine carbon cycle. Although the authors had succeeded in the DOC-14 analysis in seawater, it was necessary to use a large preprocessing apparatus, and the analysis has not been applied widely. We here report on the improvements to make this system safer and easier to handle. Following the previous method, DOC-14 in seawater was extracted as carbon dioxide by irradiating ultraviolet (UV), purified in a vacuum line, and the C-14 isotopic ratio was analysed with an accelerator mass spectrometer. As a major improvement, low-pressure mercury lamp which can irradiate UV of short wavelength (172 nm and 185 nm) suitable for decomposition of organic matter was used as UV source. By this improvement, the temperature increase in sample during processing was greatly reduced, and the size of the irradiation reactor was reduced to about half.
Otosaka, Shigeyoshi
no journal, ,
Cesium and iodine are known to behave differently in the marine environment. However, in 2011, activity ratio of I/
Cs in seabed sediment collected in the 160 km radius from the Fukushima Daiichi Nuclear Power Plant showed almost constant regardless of observation areas. This result indicated that initial deposition of I and Cs to the seafloor was not caused by gentle settling of biogenic particles, but by the contact of highly-contaminated seawater with the seafloor in a relatively short period of time. After that, the I/Cs ratio decreased in the coast and slightly increased in the offshore (water depth of 200 m to 500 m) regions. Such changes in the I/Cs ratio provide helpful information showing the transport of radionuclides near the seabed at the scale of several years.
Matsubara, Akihiro; Fujita, Natsuko; Kimura, Kenji
no journal, ,
no abstracts in English
