Singh, B.*; Basunia, M. S.*; Martin, M.*; McCutchan, E. A.*; Bara, I.*; Caballero-Folch, R.*; Canavan, R.*; Chakrabarti, R.*; Chekhovska, A.*; Grinder, M. M.*; et al.
Nuclear Data Sheets, 160, p.405 - 471, 2019/09
Yeom, Y. S.*; Han, M. C.*; Choi, C.*; Han, H.*; Shin, B.*; Furuta, Takuya; Kim, C. H.*
Health Physics, 116(5), p.664 - 676, 2019/05
Recently, Task Group 103 of the ICRP developed the mesh-type reference computational phantoms (MCRPs), which are planned for use in future ICRP dose coefficient calculation. Performance of major Monte Carlo particle transport codes (Geant4, MCNP6, and PHITS) were tested with MCRP. External and internal exposure of various particles and energies were calculated and the computational times and required memories were compared. Additionally calculation for voxel-mesh phantom was also conducted so that the influence of different mesh-representation in each code was studied. Memory usage of MRCP was as large as 10 GB with Geant4 and MCNP6 while it is much less with PHITS (1.2 GB). In addition, the computational time required for MRCP tends to increase compared to voxel-mesh phantoms with Geant4 and MCNP6 while it is equal or tends to decrease with PHITS.
Bandodkar, A. J.*; Gutruf, P.*; Choi, J.*; Lee, K.-H.*; Sekine, Yurina; Reeder, J. T.*; Jeang, W. J.*; Aranyosi, A. J.*; Lee, S. P.*; Model, J. B.*; et al.
Science Advances (Internet), 5(1), p.eaav3294_1 - eaav3294_15, 2019/01
Interest in advanced wearable technologies increasingly extends beyond systems for biophysical measurements to those that enable continuous, non-invasive monitoring of biochemical markers in biofluids. Here, we introduce battery-free, wireless microelectronic platforms that perform sensing via schemes inspired by the operation of biofuel cells. Combining these systems in a magnetically releasable manner with chrono-sampling microfluidic networks that incorporate assays based on colorimetric sensing yields thin, flexible, lightweight, skin-interfaced technologies with broad functionality in sweat analysis. A demonstration device allows simultaneous monitoring of sweat rate/loss, along with quantitative measurements of pH and of lactate, glucose and chloride concentrations using biofuel cell and colorimetric approaches.
Finsterle, S.*; Lanyon, B.*; kesson, M.*; Baxter, S.*; Bergstrm, M.*; Bockgrd, N.*; Dershowitz, W.*; Dessirier, B.*; Frampton, A.*; Fransson, .*; et al.
Geological Society, London, Special Publications, No.482, p.261 - 283, 2019/00
Nuclear waste disposal in geological formations relies on a multi-barrier concept that includes engineered components which in many cases includes a bentonite buffer surrounding waste packages and the host rock. An SKB's (Swedish Nuclear Fuel and Waste Management Co.) Modelling Task Force project facilitated to improve the overall understanding of rock - bentonite interactions, as 11 teams used different conceptualisations and modelling tools to analyse the in-situ experiment at the ps Hard Rock Laboratory. The exercise helped identify conceptual uncertainties that led to different assessments of the relative importance of the engineered and natural barrier subsystems and of aspects that need to be better understood to arrive at reliable predictions of bentonite wetting.
Phan, L. H. S.*; Ohara, Yohei*; Kawata, Ryo*; Liu, X.*; Liu, W.*; Morita, Koji*; Guo, L.*; Kamiyama, Kenji; Tagami, Hirotaka
Proceedings of 12th International Topical Meeting on Nuclear Reactor Thermal-Hydraulics, Operation and Safety (NUTHOS-12) (USB Flash Drive), 12 Pages, 2018/10
Self-leveling behavior of core fuel debris beds is one of the key phenomena for the safety assessment of core disruptive accidents (CDAs) in sodium-cooled fast reactors (SFRs). The SIMMER code has been developed for CDA analysis of SFRs, and the code has been successfully applied to numerical simulations for key thermal-hydraulic phenomena involved in CDAs as well as reactor safety assessment. However, in SIMMER's fluid-dynamics model, it is always difficult to represent the strong interactions between solid particles as well as the discrete particle characteristics. To solve this problem, a new method has been developed by combining the multi-fluid model of the SIMMER code with the discrete element method (DEM) for the solid phase to reasonably simulate the particle behaviors as well as the fluid-particle interactions in multi-phase flows. In this study, in order to validate the multi-fluid model of the SIMMER code coupled with DEM, numerical simulations were performed on a series of self-leveling experiments using a gas injection method in cylindrical particle beds. The effects of friction coefficient on the simulation results were investigated by sensitivity analysis. Though more extensive validations are needed, the reasonable agreement between simulation results and corresponding experimental data preliminarily demonstrates the potential ability of the present method in simulating the self-leveling behaviors of debris bed. It is expected that the SIMMER code coupled with DEM is a prospective computational tool for analysis of safety issues related to solid particle debris bed in SFRs.
Tang, C.*; Song, Q.*; Chang, C.-Z.*; Xu, Y.*; Onuma, Yuichi; Matsuo, Mamoru*; Liu, Y.*; Yuan, W.*; Yao, Y.*; Moodera, J. S.*; et al.
Science Advances (Internet), 4(6), p.eaas8660_1 - eaas8660_6, 2018/06
Han, M. C.*; Yeom, Y. S.*; Lee, H. S.*; Shin, B.*; Kim, C. H.*; Furuta, Takuya
Physics in Medicine and Biology, 63(9), p.09NT02_1 - 09NT02_9, 2018/05
The multi-threading computation performances of the Geant4, MCNP6, and PHITS codes were evaluated using three tetrahedral-mesh phantoms with different complexity. Photon and neutron transport simulations were conducted and the initialization time, calculation time, and memory usage were measured as a function of the number of threads N used in the simulation. The initialization time significantly increases with the complexity of the phantom, but not much with the number of the threads. For the calculation time, Geant4 showed good parallelization efficiency with multi-thread computation (30 times speed-up factor for N = 40) adopting the private tallies while saturation of the speed-up factor were observed in MCNP6 and PHITS (10 and a few times for N = 40) due to the time delay for the sharing tallies. On the other hand, Geant4 requires larger memory specification and the memory usage rapidly increases with the number of threads compared to MCNP6 or PHITS. It is notable that when compared to the other codes, the memory usage of PHITS is much smaller, regardless of both the complexity of the phantom and the number of the threads.
Saptiama, I.*; Kaneti, Y. V.*; Oveisi, H.*; Suzuki, Yoshitaka; Tsuchiya, Kunihiko; Takai, Kimiko*; Sakae, Takeji*; Pradhan, S.*; Hossain, M. S. A.*; Fukumitsu, Nobuyoshi*; et al.
Bulletin of the Chemical Society of Japan, 91(2), p.195 - 200, 2018/02
no abstracts in English
Ho, D. M. L.*; Nelwamondo, A. N.*; Okubo, Ayako; Ramebck, H.*; Song, K.*; Han, S.-H.*; Hancke, J. J.*; Holmgren, S.*; Jonsson. S.*; Kataoka, Osamu; et al.
Journal of Radioanalytical and Nuclear Chemistry, 315(2), p.353 - 363, 2018/02
The Fourth Collaborative Material Exercise (CMX-4) of the Nuclear Forensics International Technical Working Group (ITWG) registered the largest participation for this exercise in nuclear forensics, with seven of the 17 laboratories participating for the first time. In this paper, participants from five of the first-time laboratories shared their individual experience in this exercise, from preparation to analysis of samples. The exercise proved to be highly useful for testing procedures, repurposing established methods, exercising skills, and improving the understanding of nuclear forensic signatures and their interpretation trough the post-exercise review meeting.
Kristo, M. J.*; Williams, R.*; Gaffney, A. M.*; Kayzar-Boggs, T. M.*; Schorzman, K. C.*; Lagerkvist, P.*; Vesterlund, A.*; Ramebck, H.*; Nelwamondo, A. N.*; Kotze, D.*; et al.
Journal of Radioanalytical and Nuclear Chemistry, 315(2), p.425 - 434, 2018/02
In a recent international exercise, 10 international nuclear forensics laboratories successfully performed radiochronometry on three low enriched uranium oxide samples, providing 12 analytical results using three different parent-daughter pairs serving as independent chronometers. The vast majority of the results were consistent with one another and consistent with the known processing history of the materials. In general, for these particular samples, mass spectrometry gave more accurate and more precise analytical results than decay counting measurements. In addition, the concordance of the U-Pa and U-Th chronometers confirmed the validity of the age dating assumptions, increasing confidence in the resulting conclusions.
Yan, S. Q.*; Li, Z. H.*; Wang, Y. B.*; Nishio, Katsuhisa; Lugaro, M.*; Karakas, A. I.*; Makii, Hiroyuki; Mohr, P.*; Su, J.*; Li, Y. J.*; et al.
Astrophysical Journal, 848(2), p.98_1 - 98_8, 2017/10
Matsuura, Kohei*; Mizukami, Yuta*; Arai, Yuki*; Sugimura, Yuichi*; Maejima, Naoyuki*; Machida, Akihiko*; Watanuki, Tetsu*; Fukuda, Tatsuo; Yajima, Takeshi*; Hiroi, Zenji*; et al.
Nature Communications (Internet), 8, p.1143_1 - 1143_6, 2017/10
Furuta, Takuya; Sato, Tatsuhiko; Han, M. C.*; Yeom, Y. S.*; Kim, C. H.*; Brown, J. L.*; Bolch, W. E.*
Physics in Medicine and Biology, 62(12), p.4798 - 4810, 2017/06
A new function to treat tetrahedral-mesh geometry, a type of polygon-mesh geometry, was implemented in the Particle and Heavy Ion Transport code Systems (PHITS). Tetrahedral-mesh is suitable to describe complex geometry including curving shapes. In addition, construction of three-dimensional geometry using CAD software becomes possible with file format conversion. We have introduced a function to create decomposition maps of tetrahedral-mesh objects at the initial process so that the computational time for transport process can be reduced. Owing to this function, transport calculation in tetrahedral-mesh geometry can be as fast as that for the geometry in voxel-mesh with the same number of meshes. Due to adaptability of tetrahedrons in size and shape, dosimetrically equivalent objects can be represented by tetrahedrons with much fewer number of meshes compared with the voxels. For dosimetric calculation using computational human phantom, significant acceleration of the computational speed, about 4 times, was confirmed by adopting the tetrahedral mesh instead of the voxel.
Lopez-Martens, A.*; Henning, G.*; Khoo, T. L.*; Seweryniak, D.*; Alcorta, M.*; Asai, Masato; Back, B. B.*; Bertone, P. F.*; Boilley, D.*; Carpenter, M. P.*; et al.
EPJ Web of Conferences (Internet), 131, p.03001_1 - 03001_6, 2016/12
Fission barrier height and its angular-momentum dependence have been measured for the first time in the nucleus with the atomic number greater than 100. The entry distribution method, which can determine the excitation energy at which fission starts to dominate the decay process, was applied to No. The fission barrier of No was found to be 6.6 MeV at zero spin, indicating that the No is strongly stabilized by the nuclear shell effects.
Hota, S.*; Tandel, S.*; Chowdhury, P.*; Ahmad, I.*; Carpenter, M. P.*; Chiara, C. J.*; Greene, J. P.*; Hoffman, C. R.*; Jackson, E. G.*; Janssens, R. V. F.*; et al.
Physical Review C, 94(2), p.021303_1 - 021303_5, 2016/08
The decay of a = 8 isomer in Pu and the collective band structure populating the isomer are studied using deep inelastic excitations with Ti and Pb beams, respectively. Precise measurements of branching ratios in the band confirm a clean 9/27/2 for the isomer, validating the systematics of K = 8 two-quasineutron isomers observed in even-, = 150 isotones. These isomers around the deformed shell gap at = 152 provide critical benchmarks for theoretical predictions of single-particle energies in this gateway region to superheavy nuclei.
Yan, S. Q.*; Li, Z. H.*; Wang, Y. B.*; Nishio, Katsuhisa; Makii, Hiroyuki; Su, J.*; Li, Y. J.*; Nishinaka, Ichiro; Hirose, Kentaro; Han, Y. L.*; et al.
Physical Review C, 94(1), p.015804_1 - 015804_5, 2016/07
Kiriyama, Hiromitsu; Mori, Michiaki; Pirozhkov, A. S.; Ogura, Koichi; Sagisaka, Akito; Kon, Akira; Esirkepov, T. Z.; Hayashi, Yukio; Kotaki, Hideyuki; Kanasaki, Masato*; et al.
IEEE Journal of Selected Topics in Quantum Electronics, 21(1), p.1601118_1 - 1601118_18, 2015/01
This paper reviews the development of a high-contrast high-intensity petawatt-class Ti:sapphire chirped-pulse amplification (CPA) laser for research on high field science. We discuss in detail the design, performance and characterization of the laser. We also describe the on-going upgrade of the laser system and some applications for the laser in relativistic dominated laser-matter interactions.
Henning, G.*; Khoo, T. L.*; Lopez-Martens, A.*; Seweryniak, D.*; Alcorta, M.*; Asai, Masato; Back, B. B.*; Bertone, P. F.*; Boilley, D.*; Carpenter, M. P.*; et al.
Physical Review Letters, 113(26), p.262505_1 - 262505_6, 2014/12
Fission barrier heights of a shell-stabilized superheavy nucleus No have been determined as a function of spin up to 19 through the measured distribution of entry points of deexcitations in the excitation energy vs. spin plane. The fission barrier height of No was determined to be 6.0 MeV at spin 15, and 6.6 MeV at spin 0 by extrapolation. This demonstrates that the shell effect actually enlarges the fission barrier in such heavy nuclei and keeps the barrier high even at high spin.
Sako, Hiroyuki; Sugimura, Hitoshi; Ahn, J. K.*; Han, Y.*; Hasegawa, Shoichi; Hwang, S. H.*; Ichikawa, Yudai; Imai, Kenichi; Kiuchi, Ryuta*; Ozawa, Kyoichiro; et al.
Nuclear Instruments and Methods in Physics Research A, 763, p.65 - 81, 2014/11
We developed a prototype TPC for an H-dibaryon search experiment at J-PARC. To investigate its performance, we conducted tests with Ar-CH (90:10) and Ar-CF (95:5), where the former is mainly used. The detection efficiency was measured to be 98% at the beam rate up to cps/cm, and 90% at the rate of cps/cm. Based on the measured horizontal resolution of 0.19-0.46 mm at the drift length of 5-20 cm, the position resolution of better than 0.3 mm is estimated in 1 T magnetic field. The ion backflow fraction was measured to be 5% and reduced up to 3% at the gain of . The horizontal position distortion due to ion backflow in the gate operation was suppressed within mm at the beam rates up to cps/cm. On the other hand, the distortion with the gate open was measured to be mm. The distortion in the final experiment is estimated to be mm.
Sanetullaev, A.*; Tsang, M. B.*; Lynch, W. G.*; Lee, J.*; Bazin, D.*; Chan, K. P.*; Coupland, D.*; Hanzl, V.*; Hanzlova, D.*; Kilburn, M.*; et al.
Physics Letters B, 736, p.137 - 141, 2014/09
no abstracts in English