Wei, D.*; Gong, W.; Tsuru, Tomohito; Lobzenko, I.; Li, X.*; Harjo, S.; Kawasaki, Takuro; Do, H.-S.*; Bae, J. W.*; Wagner, C.*; et al.
International Journal of Plasticity, 159, p.103443_1 - 103443_18, 2022/12
Elekes, Z.*; Juhsz, M. M.*; Sohler, D.*; Sieja, K.*; Yoshida, Kazuki; Ogata, Kazuyuki*; Doornenbal, P.*; Obertelli, A.*; Achouri, N. L.*; Baba, Hidetada*; et al.
Physical Review C, 106(6), p.064321_1 - 064321_10, 2022/12
The low-lying level structure of V and V was investigated for the first time. The neutron knockout reaction and inelastic proton scattering were applied for V while the neutron knock-out reaction provided the data for V. Four and five new transitions were determined for V and V, respectively. Based on the comparison to our shell-model calculations using the Lenzi-Nowacki-Poves-Sieja (LNPS) interaction, three of the observed rays for each isotope could be placed in the level scheme and assigned to the decay of the first 11/2 and 9/2 levels. The (,) excitation cross sections for V were analyzed by the coupled-channels formalism assuming quadrupole plus hexadecapole deformations. Due to the role of the hexadecapole deformation, V could not be unambiguously placed on the island of inversion.
Enciu, M.*; Liu, H. N.*; Obertelli, A.*; Doornenbal, P.*; Nowacki, F.*; Ogata, Kazuyuki*; Poves, A.*; Yoshida, Kazuki; Achouri, N. L.*; Baba, Hidetada*; et al.
Physical Review Letters, 129(26), p.262501_1 - 262501_7, 2022/12
The one-neutron knockout from Ca was performed at 230 MeV/nucleon combined with prompt spectroscopy. The momentum distributions corresponding to the removal of and neutrons were measured. The cross sections are consistent with a shell closure at the neutron number , found as strong as at and in Ca isotopes from the same observables. The analysis of the momentum distributions leads to a difference of the root-mean-square radii of the neutron and orbitals of 0.61(23) fm, in agreement with the modified-shell-model prediction of 0.7 fm suggesting that the large root-mean-square radius of the orbital in neutron-rich Ca isotopes is responsible for the unexpected linear increase of the charge radius with the neutron number.
Hosokawa, Takayuki; Yasue, Ayumu*; Kim, J.; Kurita, Keisuke; Kanematsu, Manabu*
Konkurito Kozobutsu No Hoshu, Hokyo, Appuguredo Rombun Hokokushu (CD-ROM), 22, p.113 - 118, 2022/10
no abstracts in English
Kim, G.*; Im, S.*; Jee, H.*; Suh, H.*; Cho, S.*; Kanematsu, Manabu*; Morooka, Satoshi; Koyama, Taku*; Nishio, Yuhei*; Machida, Akihiko*; et al.
Cement and Concrete Research, 159, p.106869_1 - 106869_17, 2022/09
Walter, H.*; Colonna, M.*; Cozma, D.*; Danielewicz, P.*; Ko, C. M.*; Kumar, R.*; Ono, Akira*; Tsang, M. Y. B*; Xu, J.*; Zhang, Y.-X.*; et al.
Progress in Particle and Nuclear Physics, 125, p.103962_1 - 103962_90, 2022/07
Transport models are the main method to obtain physics information on the nuclear equation of state and in-medium properties of particles from low to relativistic-energy heavy-ion collisions. The Transport Model Evaluation Project (TMEP) has been pursued to test the robustness of transport model predictions to reach consistent conclusions from the same type of physical model. To this end, calculations under controlled conditions of physical input and set-up were performed by the various participating codes. These included both calculations of nuclear matter in a periodic box, which test individual ingredients of a transport code, and calculations of complete collisions of heavy ions. Over the years, five studies were performed within this project. They show, on one hand, that in box calculations the differences between the codes can be well understood and a convergence of the results can be reached. These studies also highlight the systematic differences between the two families of transport codes, known under the names of Boltzmann-Uehling-Uhlenbeck (BUU) and Quantum Molecular Dynamics (QMD) type codes. On the other hand, there still exist substantial differences when these codes are applied to real heavy-ion collisions. The results of transport simulations of heavy-ion collisions will have more significance if codes demonstrate that they can verify benchmark calculations such as the ones studied in these evaluations.
Tregoning, R.*; Wallace, J.*; Bouydo, A.*; Costa-Garrido, O.*; Dillstrm, P.*; Duan, X.*; Heckmann, K.*; Kim, Y.-B.*; Kim, Y.*; Kurth-Twombly, E.*; et al.
Transactions of 26th International Conference on Structural Mechanics in Reactor Technology (SMiRT-26) (Internet), 11 Pages, 2022/07
Fourteen organizations, representing eleven countries, participated in a leak-before-break (LBB) benchmark exercise that compared results from analyses among participating countries and identified the effects of weld residual stress (WRS) and crack morphology on crack opening displacement (COD), critical bending moment (CBM), and leak rate (LR) results. The participants determined whether the initial problem would meet their country's LBB acceptance criteria and then evaluated the effects of crack morphology and WRS for a prescribed crack size, geometry and loading. Six out of fourteen participants indicated that the initial problem met their LBB requirements. In the follow-on tasks, differences among the participant's CBM predictions were principally due to the material properties used in the analysis while the type of failure model chosen contributed much less. Most of the differences in the LR predictions were directly attributable to differences among the COD models, but a portion was attributable to the treatment of crack face pressure (CFP). The benchmark identified several aspects of an LBB analysis that could support a more realistic evaluation.
Tang, J.*; Seo, O.*; Rivera Rocabado, D. S.*; Koitaya, Takanori*; Yamamoto, Susumu*; Namba, Yusuke*; Song, C.*; Kim, J.*; Yoshigoe, Akitaka; Koyama, Michihisa*; et al.
Applied Surface Science, 587, p.152797_1 - 152797_8, 2022/06
The hydrogen absorption and diffusion mechanisms on cube-shaped Pd nanoparticles (NPs) which are important hydrogen-storage materials were studied using X-ray photoelectron spectroscopy and DFT calculations. In the surface region, hydrogen absorption showed almost similar behavior regardless of the NPs size. It was found that the octahedral sites are more favorable than the tetrahedral sites for hydrogen occupation. We also clarified that the hydrogen atoms absorbing on the smaller-sized Pd NPs diffuse to the subsurface more actively because of the weakened Pd-H bond by the surface disordering, which plays an important role in hydrogen adsorption at a low H pressure.
Kim, J.*; Gubler, P.; Lee, S. H.*
Physical Review D, 105(11), p.114053_1 - 114053_9, 2022/06
Koiwai, Takuma*; Wimmer, K.*; Doornenbal, P.*; Obertelli, A.*; Barbieri, C.*; Duguet, T.*; Holt, J. D.*; Miyagi, Takayuki*; Navrtil, P.*; Ogata, Kazuyuki*; et al.
Physics Letters B, 827, p.136953_1 - 136953_7, 2022/04
no abstracts in English
Zhao, Y.*; Suzuki, T.*; Iimori, T.*; Kim, H.-W.*; Ahn, J. R.*; Horio, Masafumi*; Sato, Yusuke*; Fukaya, Yuki; Kanai, T.*; Okazaki, K.*; et al.
Physical Review B, 105(11), p.115304_1 - 115304_8, 2022/03
no abstracts in English
Wei, D.*; Wang, L.*; Zhang, Y.*; Gong, W.; Tsuru, Tomohito; Lobzenko, I.; Jiang, J.*; Harjo, S.; Kawasaki, Takuro; Bae, J. W.*; et al.
Acta Materialia, 225, p.117571_1 - 117571_16, 2022/02
Kumagai, Tomohisa*; Miura, Yasufumi*; Miura, Naoki*; Marie, S.*; Almahdi, R.*; Mano, Akihiro; Li, Y.; Katsuyama, Jinya; Wada, Yoshitaka*; Hwang, J.-H.*; et al.
Journal of Pressure Vessel Technology, 144(1), p.011509_1 - 011509_18, 2022/02
To predict fracture behavior for ductile materials, some ductile fracture simulation methods different from classical approaches have been investigated based on appropriate models of ductile fracture. For the future use of the methods to overcome restrictions of classical approaches, the applicability to the actual components is of concern. In this study, two benchmark problems on the fracture tests supposing actual components were provided to investigate prediction ability of simulation methods containing parameter decisions. One was the circumferentially through-wall and surface cracked pipes subjected to monotonic bending, and the other was the circumferentially through-wall cracked pipes subjected to cyclic bending. Participants predicted the ductile crack propagation behavior by their own approaches, including FEM employed GTN yielding function with void ratio criterion, are FEM employed GTN yielding function, FEM with fracture strain or energy criterion modified by stress triaxiality, XFEM with J or delta J criterion, FEM with stress triaxiality and plastic strain based ductile crack propagation using FEM, and elastic-plastic peridynamics. Both the deformation and the crack propagation behaviors for monotonic bending were well reproduced, while few participants reproduced those for cyclic bending. To reproduce pipe deformation and fracture behaviors, most of groups needed parameters which were determined toreproduce pipe deformation and fracture behaviors in benchmark problems themselves and it is still difficult to reproduce them by using parameters only from basic materials tests.
Kim, Y. S.*; Chae, H.*; Huang, E.-W.*; Jain, J.*; Harjo, S.; Kawasaki, Takuro; Hong, S. I.*; Lee, S. Y.*
Materials, 15(4), p.1312_1 - 1312_11, 2022/02
Fukaya, Yuki; Zhao, Y.*; Kim, H.-W.*; Ahn, J.-R.*; Fukidome, Hirokazu*; Matsuda, Iwao*
Physical Review B, 104(18), p.L180202_1 - L180202_5, 2021/11
no abstracts in English
Linh, B. D.*; Corsi, A.*; Gillibert, A.*; Obertelli, A.*; Doornenbal, P.*; Barbieri, C.*; Chen, S.*; Chung, L. X.*; Duguet, T.*; Gmez-Ramos, M.*; et al.
Physical Review C, 104(4), p.044331_1 - 044331_16, 2021/10
no abstracts in English
Im, S.*; Jee, H.*; Suh, H.*; Kanematsu, Manabu*; Morooka, Satoshi; Koyama, Taku*; Nishio, Yuhei*; Machida, Akihiko*; Kim, J.*; Bae, S.*
Journal of the American Ceramic Society, 104(9), p.4803 - 4818, 2021/09
Kaburagi, Masaaki; Shimazoe, Kenji*; Kato, Masahiro*; Kurosawa, Tadahiro*; Kamada, Kei*; Kim, K. J.*; Yoshino, Masao*; Shoji, Yasuhiro*; Yoshikawa, Akira*; Takahashi, Hiroyuki*
Nuclear Instruments and Methods in Physics Research A, 1010, p.165544_1 - 165544_9, 2021/09
The number of nuclear facilities being decommissioned has been increasing worldwide, in particular following the accident of the Tokyo Electric Power Company Holdings' Fukushima Daiichi Nuclear Power Station in 2011. In these nuclear facilities, proper management of radioactive materials is required. Then, A -ray spectrometer with four segmentations using small volume CeBr scintillators with a dimension of was developed. The four scintillators were coupled to a multi-anode photomultiplier tube specific to intense radiation fields. We performed the -ray exposure study under Cs and Co radiation fields. Under the Cs radiation field, the relative energy resolution at 1375 mSv/h was the relative energy resolution at 1375 mSv/h was 9.20.05%, 8.00.08%, 8.00.03%, and 9.00.04% for the four channels, respectively.
Browne, F.*; Chen, S.*; Doornenbal, P.*; Obertelli, A.*; Ogata, Kazuyuki*; Utsuno, Yutaka; Yoshida, Kazuki; Achouri, N. L.*; Baba, Hidetada*; Calvet, D.*; et al.
Physical Review Letters, 126(25), p.252501_1 - 252501_7, 2021/06
Direct proton-knockout reactions of Sc were studied at the RIKEN Radioactive Isotope Beam Factory. Populated states of Ca were investigated through -ray and invariant-mass spectroscopy. Level energies were calculated from the nuclear shell model employing a phenomenological inter-nucleon interaction. Theoretical cross sections to states were calculated from distorted-wave impulse approximation estimates multiplied by the shell model spectroscopic factors. Despite the calculations showing a significant amplitude of excited neutron configurations in the ground-state of Sc, valence proton removals populated predominantly the ground-state of Ca. This counter-intuitive result is attributed to pairing effects leading to a dominance of the ground-state spectroscopic factor. Owing to the ubiquity of the pairing interaction, this argument should be generally applicable to direct knockout reactions from odd-even to even-even nuclei.
Kim, J.-Y.*; Kim, H.-C.*; Yang, G.-S.*; Oka, Makoto
Physical Review D, 103(7), p.074025_1 - 074025_21, 2021/04
We investigate the electromagnetic transitions of the singly charmed baryons with spin 3/2, based on a pion mean-field approach, also known as the chiral quark-soliton model, taking into account the rotational corrections and the effects of flavor SU(3) symmetry breaking. We examine the valence- and sea-quark contributions to the electromagnetic transition form factors and find that the quadrupole form factors of the sea-quark contributions dominate over those of the valence-quark ones in the smaller region, whereas the sea quarks only provide marginal contributions to the magnetic dipole transition form factors of the baryon sextet with spin 3/2. The effects of the flavor SU(3) symmetry breaking are in general very small except for the forbidden transition by -spin symmetry. We also discuss the widths of the radiative decays for the baryon sextet with spin 3/2, comparing the present results with those from other works.