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Yamaguchi, Yuji; Niikura, Megumi*; Mizuno, Rurie*; Tampo, Motonobu*; Harada, Masahide; Kawamura, Naritoshi*; Umegaki, Izumi*; Takeshita, Soshi*; Haga, Katsuhiro
Nuclear Instruments and Methods in Physics Research B, 567, p.165801_1 - 165801_11, 2025/10
Times Cited Count：0 Percentile：0.00As part of the development of a sample radioactivity calculation program, we have measured radionuclide production probabilities in negative muon nuclear capture to update experimental data and to validate a calculation dataset obtained by a Monte Carlo simulation code. The probabilities have been obtained by an activation experiment on 
Al, 
Si, 
Co, and Ta targets. The obtained probabilities expand the validation scope to the radionuclide production processes outside of the existing data coverage. By comparing the resultant probabilities with the calculated dataset, it has been revealed that the dataset is generally on the safe side in radioactivity estimation and needs to be corrected in the following three cases: (i) isomer production; (ii) radionuclide production by the multiple neutron emission; (iii) radionuclide production by particle emissions involving a proton. The present probabilities and the new findings on the correction provide valuable clues to improvements of the simulation models.
Chiu, I.-H.; Osawa, Takahito; Ninomiya, Kazuhiko*; Takeda, Shinichiro*; Takahashi, Tadayuki*; Katsuragawa, Miho*; Watanabe, Shin*; Kubo, Kenya*; Saito, Tsutomu*; Mizumoto, Kazumi*; et al.
npj Heritage Science (Internet), 13, p.154_1 - 154_9, 2025/05
Shimomura, Koichiro*; Koda, Akihiro*; Pant, A. D.*; Sunagawa, Hikaru*; Fujimori, Hiroshi*; Umegaki, Izumi*; Nakamura, Jumpei*; Fujihara, Masayoshi; Tampo, Motonobu*; Kawamura, Naritoshi*; et al.
Interactions (Internet), 245(1), p.31_1 - 31_6, 2024/12
Osawa, Takahito; Nagasawa, Shunsaku*; Ninomiya, Kazuhiko*; Takahashi, Tadayuki*; Nakamura, Tomoki*; Wada, Taiga*; Taniguchi, Akihiro*; Umegaki, Izumi*; Kubo, Kenya*; Terada, Kentaro*; et al.
ACS Earth and Space Chemistry (Internet), 7(4), p.699 - 711, 2023/04
Times Cited Count：7 Percentile：70.27(Chemistry, Multidisciplinary)The concentrations of carbon and other major elements in asteroid samples provide very important information on the birth of life on the Earth and the solar-system evolution. Elemental analysis using muonic X-rays is one of the best analytical methods to determine the elemental composition of solid materials, and notably, is the only method to determine the concentration of light elements in bulk samples in a non-destructive manner. We developed a new analysis system using muonic X-rays to measure the concentrations of carbon and other major elements in precious and expectedly tiny samples recovered from the asteroid Ryugu by spacecraft Hayabusa2. Here we report the development process of the system in 4 stages and their system configurations, The analysis system is composed of a stainless-steel analysis chamber, an acrylic glove box for manipulating asteroid samples in a clean environment, and Ge semiconductor detectors arranged to surround the analysis chamber. The performance of the analysis system, including the background level, which is crucial for the measurement, was greatly improved from the first stage to the later ones. Our feasibility study showed that the latest model of our muonic X-ray analysis system is capable of determining the carbon concentration in Hayabusa2's sample model with an uncertainty of less than 10 percent in a 6-day measurement.
Shimomura, Koichiro*; Koda, Akihiro*; Pant, A. D.*; Natori, Hiroaki*; Fujimori, Hiroshi*; Umegaki, Izumi*; Nakamura, Jumpei*; Tampo, Motonobu*; Kawamura, Naritoshi*; Teshima, Natsuki*; et al.
Journal of Physics; Conference Series, 2462, p.012033_1 - 012033_5, 2023/03
Times Cited Count：0 Percentile：73.62(Physics, Applied)Oishi, Kazuki*; Igarashi, Daisuke*; Tatara, Ryoichi*; Kawamura, Yukihiko*; Hiroi, Kosuke; Suzuki, Junichi*; Umegaki, Izumi*; Nishimura, Shoichiro*; Koda, Akihiro*; Komaba, Shinichi*; et al.
Journal of Physics; Conference Series, 2462, p.012048_1 - 012048_5, 2023/03
Times Cited Count：0 Percentile：0.00(Physics, Applied)
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Umegaki, Izumi*; Sugiyama, Jun; 7 of others*
Journal of Physical Chemistry C, 126(25), p.10506 - 10514, 2022/06
Times Cited Count：5 Percentile：33.77(Chemistry, Physical)Umegaki, Izumi*; Sugiyama, Jun; 9 of others*
Analytical Chemistry, 92(12), p.8194 - 8200, 2020/06
Times Cited Count：30 Percentile：81.67(Chemistry, Analytical)Sugiyama, Jun*; Umegaki, Izumi*; Nozaki, Hiroshi*; Higemoto, Wataru; Hamada, Koji*; Takeshita, Soshi*; Koda, Akihiro*; Shimomura, Koichiro*; Ninomiya, Kazuhiko*; Kubo, Kenya*
Physical Review Letters, 121(8), p.087202_1 - 087202_5, 2018/08
Times Cited Count：20 Percentile：71.83(Physics, Multidisciplinary)Chiu, I.-H.; Osawa, Takahito; Ninomiya, Kazuhiko*; Takeda, Shinichiro*; Katsuragawa, Miho*; Takahashi, Tadayuki*; Watanabe, Shin*; Kubo, Kenya*; Saito, Tsutomu*; Mizumoto, Kazumi*; et al.
no journal, ,
Chiu, I.-H.; Osawa, Takahito; Takeda, Shinichiro*; Katsuragawa, Miho*; Takahashi, Tadayuki*; Watanabe, Shin*; Mizumoto, Kazumi*; Saito, Tsutomu*; Kubo, Kenya*; Umegaki, Izumi*; et al.
no journal, ,
no abstracts in English
Chiu, I.-H.; Osawa, Takahito; Takeda, Shinichiro*; Katsuragawa, Miho*; Takahashi, Tadayuki*; Watanabe, Shin*; Kubo, Kenya*; Mizumoto, Kazumi*; Saito, Tsutomu*; Umegaki, Izumi*; et al.
no journal, ,
Non-destructive elemental analysis method has been developed for the materials by high-energy muon-characteristic X-rays measurement. To further improve the method, we have also utilized two-dimensional cadmium telluride hard X-ray detectors (CdTe-DSDs) for the muonic X-rays measurement to obtain the 3D elemental distribution of the sample. In this work, a 3D imaging system has been created using four CdTe-DSDs. The experiment of 3D elemental imaging for archaeological materials was performed using a negative muon beam at J-PARC/MUSE, and the three-dimensional distribution of silicon and oxygen was confirmed. This presentation introduces the research progress so far.
Tanaka, Hidekazu*; Kurita, Nubuyuki*; Umegaki, Izumi*; Ono, Toshio*; Laver, M.*; Niedermayer, Ch.*; R
egg, Ch.*; Kawamura, Seiko; Nakajima, Kenji; Kakurai, Kazuhisa
no journal, ,
Yamaguchi, Yuji; Niikura, Megumi*; Mizuno, Rurie*; Tampo, Motonobu*; Harada, Masahide; Kawamura, Naritoshi*; Umegaki, Izumi*; Takeshita, Soshi*; Haga, Katsuhiro
no journal, ,
The yield of radionuclides produced by nuclear capture of negative muons has been measured at Muon Science Establishment of Materials and Life Science Experimental Facility (MLF) to accurately estimate radioactivity of muon-irradiated samples at MLF, J-PARC. In this measurement, new data which were difficult to measure at preliminary experiment last year have been obtained by improving the negative-muon counting method.
