A5059714900- Nuclear physics research studies
- Nuclear Physics and Applications
- Atomic and Molecular Physics
- Particle accelerators and beam dynamics
- Muon and positron interactions and applications
- Astronomical and nuclear sciences
- Atomic and Subatomic Physics Research
- Mass Spectrometry Techniques and Applications
- Advanced NMR Techniques and Applications
- Nuclear reactor physics and engineering
- Particle physics theoretical and experimental studies
- Astro and Planetary Science
- Neutrino Physics Research
- Quantum Chromodynamics and Particle Interactions
- Superconducting Materials and Applications
- Radiation Detection and Scintillator Technologies
- Particle Detector Development and Performance
- Rare-earth and actinide compounds
- Advancements in Battery Materials
- Silicon and Solar Cell Technologies
- Semiconductor materials and interfaces
- Advanced Chemical Physics Studies
- Particle Accelerators and Free-Electron Lasers
- Quantum, superfluid, helium dynamics
- Isotope Analysis in Ecology
High Energy Accelerator Research Organization
2016-2025
Wako University
2021-2024
Institute of Particle and Nuclear Studies
2012-2023
Institute of Nuclear and Particle Physics
2023
University of Tsukuba
2009-2019
Institute for Basic Science
2019
Osaka Electro-Communication University
2009-2017
Japan Atomic Energy Agency
2009-2010
Tokyo Institute of Technology
2008-2010
The University of Tokyo
2010
Absolute cross sections for isotopically identified products formed in multinucleon transfer the (136)Xe+(198)Pt system at ∼8 MeV/nucleon are reported. The isotopic distributions obtained using a large acceptance spectrometer demonstrated production of "hard-to-reach" neutron-rich isotopes Z<78 around N=126 shell closure far from stability. main contribution to formation these exotic nuclei is shown arise collisions with small kinetic energy dissipation. present experimental finding...
The new isotope U241 was synthesized and systematic atomic mass measurements of nineteen neutron-rich Pa-Pu isotopes were performed in the multinucleon transfer reactions U238+Pt198 system at KISS facility. present experimental results demonstrate crucial role for accessing unexplored actinide toward N=152 shell gap this region nuclides.Received 21 November 2022Revised 26 January 2023Accepted 16 February 2023DOI:https://doi.org/10.1103/PhysRevLett.130.132502© 2023 American Physical...
The masses of ^{246}Es, ^{251}Fm, and the transfermium nuclei ^{249-252}Md ^{254}No, produced by hot- cold-fusion reactions, in vicinity deformed N=152 neutron shell closure, have been directly measured using a multireflection time-of-flight mass spectrograph. ^{246}Es ^{249,250,252}Md were for first time. Using ^{249,250}Md as anchor points α decay chains, heavier nuclei, up to ^{261}Bh ^{266}Mt, determined. These new compared with theoretical global models demonstrated be good agreement...
187Ta (𝑍=73, 𝑁=114) is located in the neutron-rich 𝐴≈190 region where a prolate-to-oblate shape transition via triaxial softness predicted to take place. A preceding work on 𝐾𝜋=(25/2−) isomer and rotational band which decays carried out by same collaboration revealed that axial symmetry slightly violated this nucleus. This paper focuses higher-lying isomer, was previously identified at 2933(14) keV mass measurements with Experimental Storage Ring GSI. The of interest has been populated...
The elastic scattering of the weakly bound radioactive nuclei $^{8}\mathrm{B}$ and $^{7}\mathrm{Be}$ from a $^{208}\mathrm{Pb}$ target was measured for first time in energy range around Coulomb barrier. data were analyzed using optical model continuum discretized coupled channels (CDCC) formalisms. reaction cross sections extracted fits clearly indicate remarkably enhanced probability very (${S}_{p}=137.5\phantom{\rule{0.16em}{0ex}}\mathrm{keV}$) compared to similar mass interacting with...
The atomic masses of ^{55}Sc, ^{56,58}Ti, and ^{56-59}V have been determined using the high-precision multireflection time-of-flight technique. radioisotopes produced at RIKEN's Radioactive Isotope Beam Factory (RIBF) delivered to novel designed gas cell system, which has recently commissioned downstream ZeroDegree spectrometer following BigRIPS separator. For ^{56,58}Ti ^{56-59}V, mass uncertainties reduced down order 10 keV, shedding new light on N=34 shell effect in Ti V isotopes by first...
A search for new neutron-rich isotopes near the $N=60$ isotones $^{92}\mathrm{Ge}$ and $^{93}\mathrm{As}$ has been performed using a 345 MeV/nucleon $^{238}\mathrm{U}$ beam at RIKEN Nishina Center RI Beam Factory. Fission fragments produced were analyzed identified in flight large-acceptance two-stage separator BigRIPS. We have observed total of 15 isotopes: $^{84}\mathrm{Cu}, ^{86,87}\mathrm{Zn}, ^{88,89}\mathrm{Ga}, ^{91,92}\mathrm{Ge}, ^{93,94,95}\mathrm{As}, ^{96,97}\mathrm{Se},...
Precise mass measurements of refractory nuclei produced by multinucleon transfer reactions a136Xe beam and natIr target were conducted at the KISS (KEK Isotope Separation System) facility, using a multireflection time-of-flight spectrograph. The study encompasses ions with numbers 𝐴=188,189,190,192, atomic 𝑍=74–79. Our findings show good agreement between evaluated masses, excluding 192Re, known values, within specified error margins. assessment includes reevaluation rejected value for 189W...
A rotational band with five $\gamma$-ray transitions ranging from 2$^{+}$ to 12$^{+}$ states was identified in $^{40}$Ar. This is linked through $\gamma$ the excited 2$^{+}$, 4$^{+}$ and 6$^{+}$ levels low-lying states; this determines excitation energy spin-parity of band. The deduced transition quadrupole moment 1.45$^{+0.49}_{-0.31} eb$ indicates that has a superdeformed shape. nature revealed by cranked Hartree--Fock--Bogoliubov calculations multiparticle--multihole configuration assigned
We present the first direct measurement of atomic mass a superheavy nuclide. Atoms $^{257}$Db ($Z$=105) were produced online at RIKEN Nishina Center for Accelerator-Based Science using fusion-evaporation reaction $^{208}$Pb($^{51}$V, 2n)$^{257}$Db. The gas-filled recoil ion separator GARIS-II was used to suppress both unreacted primary beam and some transfer products, prior delivering energetic ions helium stopping cell wherein they thermalized. Thermalized $^{257}$Db$^{3+}$ then transferred...
The magnetic dipole moment and mean-square charge radius of $^{199g}\mathrm{Pt}$ $({I}^{\ensuremath{\pi}}=$ $5/{2}^{\ensuremath{-}},{t}_{1/2}=30.8$ min) ground state $^{199m}\mathrm{Pt}$ $({E}_{\mathrm{ex}}=424$ keV, ${I}^{\ensuremath{\pi}}=$ (13/2)${}^{+},{t}_{1/2}=13.6$ s) isomeric are evaluated for the first time from investigations hyperfine splitting ${\ensuremath{\lambda}}_{1}=248.792$ nm transition by in-gas-cell laser ionization spectroscopy. Ground states neutron-rich...
We performed in-gas-cell laser ionization spectroscopy of $^{194,196}\mathrm{Os}$, which were produced by multinucleon transfer reactions at the KEK Isotope Separation System (KISS). The nuclei interest identified through $\ensuremath{\beta}$-decay and a newly applied multireflection time-of-flight mass spectrograph (MRTOF-MS). From study resonance spectra, isotope shifts (ISs) transition ${\ensuremath{\lambda}}_{1}=247.758$ nm for $^{194}\mathrm{Os}$ $^{196}\mathrm{Os}$ measured first time....
The atomic masses of Ag111,113, Pd111–113, Rh111–113, Ru111–113, and Mo111,112 have been measured during the online commissioning experiments ZeroDegree multi-reflection time-of-flight Mass Spectrograph (ZD MRTOF-MS) at RIKEN RI beam factory. mass Mo112 has determined. For previously known masses, a good agreement between our results 2020 Atomic Evaluation observed in most cases. determined two-neutron separation energies for Mo isotopes up to N=70 show smooth trend. In this work, performed...
Mass-separated ^{187}Ta_{114} in a high-spin isomeric state has been produced for the first time by multinucleon transfer reactions, employing an argon gas-stopping cell and laser ionization. Internal γ rays revealed T_{1/2}=7.3±0.9 s isomer at 1778±1 keV, which decays through rotational band with perturbations associated approach to prolate-oblate shape transition. Model calculations show less influence from triaxiality compared heavier elements same mass region. The isomer-decay reduced E2...