Ionic radii in halites

Vauchy, R.; Hirooka, Shun; Murakami, Tatsutoshi

Materialia, 32, p.101943_1 - 101943_8, 2023/12

https://doi.org/10.1016/j.mtla.2023.101943

The Investigations of the -wave states combining quark model and lattice QCD in the coupled channel framework

Yang, Z.*; Wang, G.-J.*; Wu, J.-J.*; Oka, Makoto; Zhu, S.-L.*

Journal of High Energy Physics (Internet), 2023(1), p.058_1 - 058_19, 2023/01

https://doi.org/10.1007/JHEP01(2023)058

Combining the quark model, the quark-pair-creation mechanism and interaction, we have investigated the near-threshold -wave states in the framework of the Hamiltonian effective field theory. With the heavy quark flavor symmetry, all the parameters are determined in the sector by fitting the lattice data. The masses of the bottom-strange partners of the and are predicted, which are well consistent with the lattice QCD simulation. The two -wave states are the mixtures of the bare core and component. Moreover, we find a crossing point between the energy levels with and without the interaction Hamiltonian in the finite volume spectrum in the case, which corresponds to a CDD (Castillejo-Dalitz-Dyson) zero in the -matrix of the scattering. This CDD zero will help deepen the insights of the near-threshold states and can be examined by future lattice calculation.

Free-surface flow simulations with floating objects using lattice Boltzmann method

Watanabe, Seiya*; Kawahara, Jun*; Aoki, Takayuki*; Sugihara, Kenta; Takase, Shinsuke*; Moriguchi, Shuji*; Hashimoto, Hirotada*

Engineering Applications of Computational Fluid Mechanics, 17(1), p.2211143_1 - 2211143_23, 2023/00

https://doi.org/10.1080/19942060.2023.2211143

In tsunami inundations or slope disasters of heavy rain, a lot of floating debris or driftwood logs are included in the flows. The damage to structures from solid body impacts is more severe than the damage from the water pressure. In order to study free-surface flows that include floating debris, developing a high-accurate simulation code of free-surface flows with high performance for large-scale computations is desired. We propose the single-phase free-surface flow model based on the cumulant lattice Boltzmann method coupled with a particle-based rigid body simulation. The discrete element method calculates the contact interaction between solids. An octree-based AMR (Adaptive Mesh Refinement) method is introduced to improve computational accuracy and time-to-solution. High-resolution grids are assigned near the free surfaces and solid boundaries. We conducted two kinds of tsunami flow experiments in the 15 and 70 m water tanks at Hachinohe Institute of Technology and Kobe University to validate the accuracy of the proposed model. The simulation results have shown good agreement with the experiments for the drifting speed, the number of trapped wood pieces, and the stacked angles.

Quantum critical spin-liquid-like behavior in the = quasikagome-lattice compound CeRhPdSn investigated using muon spin relaxation and neutron scattering

Tripathi, R.*; Adroja, D. T.*; Ritter, C.*; Sharma, S.*; Yang, C.*; Hillier, A. D.*; Koza, M. M.*; Demmel, F.*; Sundaresan, A.*; Langridge, S.*; et al.

Physical Review B, 106(6), p.064436_1 - 064436_17, 2022/08

https://doi.org/10.1103/PhysRevB.106.064436

GPU optimization of lattice Boltzmann method with local ensemble transform Kalman filter

Hasegawa, Yuta; Imamura, Toshiyuki*; Ina, Takuya; Onodera, Naoyuki; Asahi, Yuichi; Idomura, Yasuhiro

Proceedings of 13th Workshop on Latest Advances in Scalable Algorithms for Large-Scale Heterogeneous Systems (ScalAH22) (Internet), p.10 - 17, 2022/00

https://doi.org/10.1109/ScalAH56622.2022.00007

The ensemble data assimilation of computational fluid dynamics simulations based on the lattice Boltzmann method (LBM) and the local ensemble transform Kalman filter (LETKF) is implemented and optimized on a GPU supercomputer based on NVIDIA A100 GPUs. To connect the LBM and LETKF parts, data transpose communication is optimized by overlapping computation, file I/O, and communication based on data dependency in each LETKF kernel. In two dimensional forced isotropic turbulence simulations with the ensemble size of and the number of grid points of , the optimized implementation achieved speedup from the naive implementation, in which the LETKF part is not parallelized. The main computing kernel of the local problem is the eigenvalue decomposition (EVD) of real symmetric dense matrices, which is computed by a newly developed batched EVD in EigenG. The batched EVD in EigenG outperforms that in cuSolver, and speedup was achieved.

Evaluation of the minimum critical amount for heterogeneous lattice systems composed of fuel rods utilized in low-power water-moderated research and test reactors by using continuous-energy Monte Carlo code MVP with JENDL-4.0

Yanagisawa, Hiroshi

JAEA-Technology 2021-023, 190 Pages, 2021/11

JAEA-Technology-2021-023.pdf:5.25MB

Computational analyses on nuclear criticality characteristics were carried out for heterogeneous lattice systems composed of water moderator and fuel rods utilized in low-power research and test reactors, in which the depletion of fuel due to burnup is relatively small, by using the continuous-energy Monte Carlo code MVP Version 2 with the evaluated nuclear data library JENDL-4.0. In the analyses, the minimum critical number of fuel rods was evaluated using calculated neutron multiplication factors for the heterogeneous systems of the uranium dioxide fuel rod in the Static Experiments Critical Facility (STACY) and the Tank-type Critical Assembly (TCA), and the uranium-zirconium hydride fuel rod in the Nuclear Safety Research Reactor (NSRR). In addition, six sorts of the ratio of reaction rates, which are components of neutron multiplication factors, were calculated in the analyses to explain the variation of neutron multiplication factors with the ratio of water moderator to fuel volume in a unit fuel rod cell. Those results of analyses are considered to be useful for the confirmation of reasonableness and validity of criticality safety measures as data showing criticality characteristics for water-moderated heterogeneous lattice systems composed of the existing fuel rods in research and test reactors, of which criticality data are not sufficiently provided by the Criticality Safety Handbook.

Charmed baryon spectrum from lattice QCD near the physical point

Bahtiyar, H.*; Can, K. U.*; Erkol, G.*; Gubler, P.; Oka, Makoto; Takahashi, Toru*

Physical Review D, 102(5), p.054513_1 - 054513_18, 2020/09

AA2020-0041.pdf:2.4MB

https://doi.org/10.1103/PhysRevD.102.054513

Spectrum of the ground state and excited states of charmed baryons was evaluated in the lattice QCD, the first principle of hadronic interaction. We deliver the spectrum of the positive and negative parity baryons with one, two or three charmed quarks. A variational approach was employed by the use of multiple operators with different Dirac matrix configurations and the smearings.

Radiative transitions of singly and doubly charmed baryons in lattice QCD

Bahtiyar, H.*; Can, K. U.*; Erkol, G.*; Oka, Makoto; Takahashi, Toru*

JPS Conference Proceedings (Internet), 26, p.022027_1 - 022027_4, 2019/11

https://doi.org/10.7566/JPSCP.26.022027

Transition amplitude of spin 3/2 single and double-charm baryon to spin 1/2 ground state was evaluated in the lattice QCD, the first principle.

Tuning strain-induced -to- martensitic transformation of biomedical Co-Cr-Mo alloys by introducing parent phase lattice defects

Mori, Manami*; Yamanaka, Kenta*; Sato, Shigeo*; Tsubaki, Shinki*; Sato, Kozue*; Kumagai, Masayoshi*; Imafuku, Muneyuki*; Shobu, Takahisa; Chiba, Akihiko*

Journal of the Mechanical Behavior of Biomedical Materials, 90, p.523 - 529, 2019/02

https://doi.org/10.1016/j.jmbbm.2018.10.038

Elastically-homogeneous lattice models of damage in geomaterials

Asahina, Daisuke*; Aoyagi, Kazuhei; Kim, K.*; Birkholzer, J.*; Birkholzer, J. T.*; Bolander, J. E.*

Computers and Geotechnics, 81, p.195 - 206, 2017/01

https://doi.org/10.1016/j.compgeo.2016.08.015