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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：4 Percentile：93.95(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：0.2(Physics, Applied)Okutsu, Kenichi*; Yamashita, Takuma*; Kino, Yasushi*; Nakashima, Ryota*; Miyashita, Konan*; Yasuda, Kazuhiro*; Okada, Shinji*; Sato, Motoyasu*; Oka, Toshitaka; Kawamura, Naritoshi*; et al.
Fusion Engineering and Design, 170, p.112712_1 - 112712_4, 2021/09
Times Cited Count：3 Percentile：45.99(Nuclear Science & Technology)A muonic molecule which consists of two hydrogen isotope nuclei (deuteron (d) or tritium (t)) and a muon decays immediately via nuclear fusion and the muon will be released as a recycling muon, and start to find another hydrogen isotope nucleus. The reaction cycle continues until the muon ends up its lifetime of 2.2 
s. Since the muon does not participate in the nuclear reaction, the reaction is so called a muon catalyzed fusion (CF). The recycling muon has a particular kinetic energy (KE) of the muon molecular orbital when the nuclear reaction occurs. Since the KE is based on the unified atom limit where distance between two nuclei is zero. A precise few-body calculation estimating KE distribution (KED) is also in progress, which could be compared with the experimental results. In the present work, we observed recycling muons after CF reaction.
Yamashita, Takuma*; Okutsu, Kenichi*; Kino, Yasushi*; Nakashima, Ryota*; Miyashita, Konan*; Yasuda, Kazuhiro*; Okada, Shinji*; Sato, Motoyasu*; Oka, Toshitaka; Kawamura, Naritoshi*; et al.
Fusion Engineering and Design, 169, p.112580_1 - 112580_5, 2021/08
Times Cited Count：3 Percentile：45.99(Nuclear Science & Technology)A muon () having 207 times larger mass of electron and the same charge as the electron has been known to catalyze a nuclear fusion between deuteron (d) and triton (t). These two nuclei are bound by and form a muonic hydrogen molecular ion, dt. Due to the short inter-nuclear distance of dt, the nuclear fusion, d +t
+ n + 17.6 MeV, occurs inside the molecule. This reaction is called muon catalyzed fusion (CF). Recently, the interest on CF is renewed from the viewpoint of applications, such as a source of high-resolution muon beam and mono-energetic neutron beam. In this work, we report a time evolution calculation of CF in a two-layered hydrogen isotope target.
X raysOkumura, Takuma*; Azuma, Toshiyuki*; Bennet, D. A.*; Caradonna, P.*; Chiu, I. H.*; Doriese, W. B.*; Durkin, M. S.*; Fowler, J. W.*; Gard, J. D.*; Hashimoto, Tadashi; et al.
Physical Review Letters, 127(5), p.053001_1 - 053001_7, 2021/07
Times Cited Count：13 Percentile：79.44(Physics, Multidisciplinary)We observed electronic X rays emitted from muonic iron atoms using a superconducting transition-edge-type sensor microcalorimeter. The energy resolution of 5.2 eV in FWHM allowed us to observe the asymmetric broad profile of the electronic characteristic 
and 
X rays together with the hypersatellite X rays around 6 keV. This signature reflects the time-dependent screening of the nuclear charge by the negative muon and the 
-shell electrons, accompanied by electron side-feeding. Assisted by a simulation, this data clearly reveals the electronic - and -shell hole production and their temporal evolution during the muon cascade process.
Liao, W.*; Hashimoto, Masanori*; Manabe, Seiya*; Watanabe, Yukinobu*; Abe, Shinichiro; Tampo, Motonobu*; Takeshita, Soshi*; Miyake, Yasuhiro*
IEEE Transactions on Nuclear Science, 67(7), p.1566 - 1572, 2020/07
Times Cited Count：0 Percentile：0.01(Engineering, Electrical & Electronic)Muon-induced single event upset (SEU) is predicted to increase with technology scaling. The angle of incidence of terrestrial muons is not always perpendicular to the chip surface. Consequently, the impact of the angle of incidence of muons on SEUs should be evaluated. This study conducts negative muon irradiation tests on bulk SRAM and FDSOI SRAM at two angles of incidence: 0 degree (vertical) and 45 degree (tilted). The tilted incidence drifts the muon energy peak to a higher energy. Moreover, the SEU characteristics (i.e., such as the voltage dependences of the SEU cross sections and multiple cells upset patterns) between the vertical and tilted incidences are similar.
Manabe, Seiya*; Watanabe, Yukinobu*; Liao, W.*; Hashimoto, Masanori*; Nakano, Keita*; Sato, Hikaru*; Kin, Tadahiro*; Abe, Shinichiro; Hamada, Koji*; Tampo, Motonobu*; et al.
IEEE Transactions on Nuclear Science, 65(8), p.1742 - 1749, 2018/08
Times Cited Count：8 Percentile：62.99(Engineering, Electrical & Electronic)Recently, the malfunction of microelectronics caused by secondary cosmic-ray muon is concerned as semiconductor devices become sensitive to radiation. In this study, we have performed muon irradiation testing for 65-nm ultra-thin body and thin buried oxide (UTBB-SOI) SRAMs in the Japan Proton Accelerator Research Complex (J-PARC), in order to investigate dependencies of single event upset (SEU) cross section on incident muon momentum and supply voltage. It was found that the SEU cross section by negative muon are approximately two to four times larger than those by positive muon in the momentum range from 35 MeV/c to 39 MeV/c. The supply voltage dependence of muon-induced SEU cross section was measured with the momentum of 38 MeV/c. SEU cross sections decrease with increasing supply voltage, but the decreasing of SEU cross section by negative muon is gentler than that by positive muon. Experimental data of positive and negative muon irradiation with the momentum of 38 MeV/c were analyzed by PHITS. It was clarified that the negative muon capture causes the difference between the SEU cross section by negative muon and that by positive muon.
Liao, W.*; Hashimoto, Masanori*; Manabe, Seiya*; Watanabe, Yukinobu*; Abe, Shinichiro; Nakano, Keita*; Sato, Hikaru*; Kin, Tadahiro*; Hamada, Koji*; Tampo, Motonobu*; et al.
IEEE Transactions on Nuclear Science, 65(8), p.1734 - 1741, 2018/08
Times Cited Count：14 Percentile：81.7(Engineering, Electrical & Electronic)Soft error induced by secondary cosmic-ray muon is concerned since susceptibility of semiconductor device to soft error increases with the scaling of technology. In this study, we have performed irradiation tests of muons on 65-nm bulk CMOS SRAM in the Japan Proton Accelerator Research Complex (J-PARC) and measured soft error rate (SER) to investigate mechanism of muon-induced soft errors. It was found that SER by negative muon increases above 0.5 V supply voltage, although SER by positive muon increases monotonically as the supply voltage lowers. SER by negative muon also increases with forward body bias. In addition, negative muon causes large multiple cell upset (MCU) of more than 20 bits and the ratio of MCU events to all the events is 66% at 1.2V supply voltage. These tendencies indicate that parasitic bipolar action (PBA) is highly possible to contribute to SER by negative muon. Experimental data are analyzed by PHITS. It was found that negative muon can deposit larger charge than positive muon, and such events that can deposit large charge may trigger PBA.
Tampo, Motonobu*; Hamada, Koji*; Kawamura, Naritoshi*; Inagaki, Makoto*; Ito, Takashi; Kojima, Kenji*; Kubo, Kenya*; Ninomiya, Kazuhiko*; Strasser, P.*; Yoshida, Go*; et al.
JPS Conference Proceedings (Internet), 8, p.036016_1 - 036016_6, 2015/09
Khumaeni, A.; Tampo, Motonobu; Akaoka, Katsuaki; Miyabe, Masabumi; Wakaida, Ikuo
Optics Express (Internet), 21(24), p.29755 - 29768, 2013/12
Times Cited Count：51 Percentile：91.11(Optics)Intensified microwave coupled by a loop antenna (diameter of 3 mm) has been employed to enhance the laser-induced breakdown spectroscopy (LIBS) emission. In this method, a laser plasma was induced on Gd
O
sample at a reduced pressure by focusing a pulsed Nd:YAG laser (532 nm, 10 ns, 5 mJ) at a local point, at which electromagnetic field was produced by introducing microwave radiation using loop antenna. The plasma emission was significantly enhanced by absorbing the microwave radiation, resulting in high-temperature plasma and long-lifetime plasma emission. By using this method, the enhancement of Gd lines was up to 32 times, depending upon the emission lines observed. A linear calibration curve of Ca contained in the GdO sample was made. The detection limit of Ca was approximately 2 mg/kg. This present method is very useful for identification of trace elements in nuclear fuel and radioactive materials.
Miyabe, Masabumi; Oba, Masaki; Iimura, Hideki; Akaoka, Katsuaki; Maruyama, Yoichiro; Oba, Hironori; Tampo, Motonobu; Wakaida, Ikuo
Applied Physics A, 112(1), p.87 - 92, 2013/07
Times Cited Count：29 Percentile：74.44(Materials Science, Multidisciplinary)A uranium oxide sample was ablated by 2nd harmonic radiation from a Nd:YAG laser at a fluence of 0.5 J/cm
. The temporal evolution of the ablation plume was investigated in vacuum and helium environments. In vacuum, the flow velocity perpendicular to the sample surface was determined to be 2.7 km/s for neutral atoms and 4.0 km/s for singly charged atoms. From the evolution of the plume in helium we found that an observation time of 3-5 s and an observation height of about 2.5 mm are most suited for obtaining higher sensitivity. Observation times less than 3 s were unsuitable for precise isotope analysis since the spectral modifications arising from the Doppler splitting effect are different between the two uranium isotopes. Using the established conditions, we evaluated the calibration curve linearity, limit of detection, and precision for three samples having different abundances of 
U.
Fukuda, Yuji; Sakaki, Hironao; Kanasaki, Masato; Yogo, Akifumi; Jinno, Satoshi; Tampo, Motonobu*; Faenov, A. Ya.*; Pikuz, T. A.*; Hayashi, Yukio; Kando, Masaki; et al.
Proceedings of SPIE, Vol.8779 (Internet), p.87790F_1 - 87790F_7, 2013/05
Times Cited Count：0 Percentile：0.05(Engineering, Biomedical)We demonstrate a new ion diagnosis method for high energy ions by utilizing a combination of a single CR-39 detector and plastic plates, which enables to detect high energy ions beyond the detection threshold limit of the CR-39. This detection method coupled with a magnetic spectrometer is applied to identify high energy ions of 50 MeV per nucleon in laser-driven ion acceleration experiments using cluster-gas targets.
Miyabe, Masabumi; Oba, Masaki; Iimura, Hideki; Akaoka, Katsuaki; Maruyama, Yoichiro; Oba, Hironori; Tampo, Motonobu; Wakaida, Ikuo
Hyperfine Interactions, 216(1-3), p.71 - 77, 2013/04
Times Cited Count：15 Percentile：96.74(Physics, Atomic, Molecular & Chemical)To determine experimental conditions suitable for isotope analysis, we studied the plume dynamics of uranium. A uranium oxide sample was ablated by 2nd harmonic radiation from a Nd:YAG laser at a fluence of 0.5 J/cm. The temporal evolution of the ablation plume was investigated in 800 Pa helium environment. It was found that the observation at 3-5
10
s after the ablation at the height of about 2.5 mm are most suited for obtaining higher sensitivity. Using the established conditions, we obtained the limit of detection of the isotope ratio (U/
U) to be 0.01%. In addition, the limit of detection of elemental abundance of uranium in uranium glass was also evaluated.
Fukuda, Yuji; Sakaki, Hironao; Kanasaki, Masato; Yogo, Akifumi; Jinno, Satoshi; Tampo, Motonobu; Faenov, A. Ya.*; Pikuz, T.; Hayashi, Yukio; Kando, Masaki; et al.
Radiation Measurements, 50, p.92 - 96, 2013/03
Times Cited Count：12 Percentile：67.14(Nuclear Science & Technology)A new diagnosis method for high energy ions utilizing a single CR-39 detector mounted on plastic plates is demonstrated to identify the presence of the high energy component beyond the CR-39's detection threshold limit. On irradiation with a 25 MeV per nucleon He ion beam from conventional rf-accelerators, a large number of etch pits having elliptical opening shapes are observed on the rear surface. Detailed investigations reveal that these etch pits are created by heavy ions inelastically backscattered from the plastic plates. This ion detection method is applied to laser-driven ion acceleration experiments using cluster-gas targets, and acceleration of ions with energies up to 50 MeV per nucleon are identified.
Miyabe, Masabumi; Oba, Masaki; Iimura, Hideki; Akaoka, Katsuaki; Maruyama, Yoichiro; Oba, Hironori; Tampo, Motonobu; Wakaida, Ikuo
Journal of Applied Physics, 112(12), p.123303_1 - 123303_10, 2012/12
Times Cited Count：16 Percentile：55.56(Physics, Applied)The temporal evolution of the ablation plume of cerium was investigated by absorption spectroscopy. Cerium oxide pellets were ablated in helium by 2nd harmonic radiation from a YAG laser. The lateral velocity of the plume was determined from the magnitude of the Doppler splitting of the absorption spectra. The velocities of neutral and ionized atoms were systematically investigated by varying several parameters. Temporal profiles of the transmittance signal were measured by detuning the probe laser frequency from the atomic resonant frequency in order to evaluate the temporal variation of the lateral velocity. On the basis of the drag force model, the slowing coefficients for atomic and ionic species in helium were evaluated along with the lateral velocity in a vacuum. This study may help in understanding the plume dynamics effect on deposited film properties as well as optimizing experimental conditions for ablation-based spectroscopic analysis.
Kanasaki, Masato; Yamauchi, Tomoya*; Fukuda, Yuji; Sakaki, Hironao; Hori, Toshihiko*; Tampo, Motonobu; Kurashima, Satoshi; Kamiya, Tomihiro; Oda, Keiji*; Kondo, Kiminori
AIP Conference Proceedings 1465, p.142 - 147, 2012/07
Times Cited Count：1 Percentile：46.45(Physics, Applied)A new diagnosis method has been developed utilizing back scattered particles for high energy intense ion beams. The CR-39 detector mounted on the uniform back-scatterer was irradiated with 
He
ions with an energy 25 MeV/n, which is never recorded as etchable track in CR-39. We found that it is possible to diagnose the high energy intense ion beams by analyzing the etch pits created on the rear surface of CR-39 that directly contacted on the back-scatterers. It turns out that most of etch pits in the rear surface are made by the backscattered particles through the investigation of the growth pattern of each etch pit with multi-step etching technique. This method allows simple diagnosis of the ion beam profile and the presence of high energy component of ions beyond the detection threshold limit of the CR-39 in mixed radiation fields such as laser-driven ion acceleration experiments.
Kanasaki, Masato; Fukuda, Yuji; Sakaki, Hironao; Hori, Toshihiko; Tampo, Motonobu; Kondo, Kiminori; Kurashima, Satoshi; Kamiya, Tomihiro; Oda, Keiji*; Yamauchi, Tomoya*
Japanese Journal of Applied Physics, 51(5), p.056401_1 - 056401_4, 2012/05
Times Cited Count：6 Percentile：26.76(Physics, Applied)A single CR-39 detector mounted on plastic plates is irradiated with a 100 MeV He ion beam. Although the beam energy is much greater than the detection threshold limit of the CR-39 detector, a large number of etch pits having elliptical openings are observed on the rear surface. Detailed investigations reveal that these etch pits are created by heavy ions inelastically backscattered from the plastic plates. This method allows a simple diagnosis of the ion beam profile and the presence of the high-energy component beyond the detection threshold limit of the CR-39 detector, especially in mixed-radiation fields such as laser-driven ion acceleration experiments.
Fukuda, Yuji; Tampo, Motonobu; Sakaki, Hironao; Kondo, Kiminori; Kanasaki, Masato; Yamauchi, Tomoya*
Hoshasen, 37(3), p.169 - 172, 2011/10
In the laser-driven ion acceleration experiments, it is almost impossible to predict maximum ion energy in advance, because the maximum energy varies according to experimental condition. Recently, solid state nuclear track detectors such as CR-39 detectors have been extensively used in laser-driven ion acceleration experiments. This is because the CR-39 have a great advantage that they are insensitive to high energy photons and electrons and capable of detecting only ions. However, the CR-39 cannot detect fast ions with energies beyond its detection threshold limit. A stack of CR-39 or a method utilizing backscattered particles are developed to detect high energy ions. Moreover, vacuum effects on CR-39 make it difficult to identify ion energies and ion species. We introduce applications of CR-39 detectors in laser-driven particle acceleration experiments in JAEA-KPSI.
Kanasaki, Masato; Yamauchi, Tomoya*; Fukuda, Yuji; Sakaki, Hironao; Hori, Toshihiko*; Tampo, Motonobu; Kondo, Kiminori; Kurashima, Satoshi; Kamiya, Tomihiro
Hoshasen, 37(3), p.127 - 132, 2011/10
A diagnosis method has been developed utilizing back scattered particles with the single PADC detector for high energy intense ion beams. The PADC detector mounted on the uniform back-scatterer was irradiated with He ions with an energy of 100 MeV, which is never recorded as etchable tracks in PADC. It turns out that most of etch pits in the rear surface are made by the back-scattered particles through the investigation of the growth pattern of each etch pit. This method allows simple diagnosis of the ion beam profile and intensity distribution with wide energy range in mixed radiation fields such as laser-driven ion acceleration experiments.
Fukuda, Yuji; Faenov, A.*; Tampo, Motonobu; Pikuz, T.*; Nakamura, Tatsufumi; Kando, Masaki; Hayashi, Yukio; Yogo, Akifumi; Sakaki, Hironao; Kameshima, Takashi*; et al.
Progress in Ultrafast Intense Laser Science VII, p.225 - 240, 2011/05
http://www.springer.com/physics/atomic,+molecular,+optical+%26+plasma+physics/book/978-3-642-18326-3We present substantial enhancement of the accelerated ion energies up to 10-20 MeV per nucleon by utilizing the unique properties of the cluster-gas target irradiated with 40-fs laser pulses of only 150 mJ energy, corresponding to approximately tenfold increase in the ion energies compared to previous experiments using thin foil targets. A particle-in-cell simulation infers that the high energy ions are generated at the rear side of the target due to the formation of a strong dipole vortex structure in sub-critical density plasmas. The demonstrated method can be important in the development of efficient laser ion accelerators for hadron therapy and other applications.