A5059620882- Nuclear physics research studies
- Quantum Chromodynamics and Particle Interactions
- Quantum, superfluid, helium dynamics
- Atomic and Molecular Physics
- Advanced NMR Techniques and Applications
- Advanced Chemical Physics Studies
- Nuclear Physics and Applications
- Particle physics theoretical and experimental studies
- Atomic and Subatomic Physics Research
- Superconducting Materials and Applications
- Cold Atom Physics and Bose-Einstein Condensates
- High-Energy Particle Collisions Research
- Astronomical and nuclear sciences
- Astro and Planetary Science
- Scientific Research and Discoveries
- Nuclear reactor physics and engineering
- Particle accelerators and beam dynamics
- Geophysics and Gravity Measurements
- Inorganic Fluorides and Related Compounds
- Computational Physics and Python Applications
- Quantum chaos and dynamical systems
- Pulsars and Gravitational Waves Research
- Black Holes and Theoretical Physics
- Random lasers and scattering media
- High-pressure geophysics and materials
Osaka University
2015-2024
Osaka Institute of Technology
2015-2024
High Energy Accelerator Research Organization
2011-2020
Nihon University
2011-2020
Japan Proton Accelerator Research Complex
2014-2020
Hokkaido University
1997-2003
Resonance phenomena in quantum physics are very familiar many fields of physics, but we have not yet obtained a complete physical understanding, mathematical description or computational treatment, especially the case many-body resonances. Recently, experimental developments concerning unstable nuclear and heavy-ion reactions, much interest has been concentrated on resonance problems. In last quarter century, theoretical treatments resonances experienced great development through application...
Isoscalar monopole strength function in ${}^{16}$O up to ${E}_{x}\ensuremath{\simeq}40$ MeV is discussed. We found that the fine structures at low-energy region ${E}_{x}\ensuremath{\simeq}16$ experimental obtained by ${}^{16}$O$(\ensuremath{\alpha},{\ensuremath{\alpha}}^{\ensuremath{'}})$ reaction can be rather satisfactorily reproduced within framework of $4\ensuremath{\alpha}$ cluster model, while gross three bump observed higher energy...
The transition strength for Coulomb breakup of ${}^{6}\mathrm{He}$ into ${}^{4}\mathrm{He}+n+n$ three-body unbound states is studied in the framework complex scaling method (CSM). We propose a to analyze which CSM utilized decompose strengths resonance and continuum components. calculate contributions $E1$ $E2$ transitions, not only from resonances, but also two-body ${\mathrm{``}}^{5}\mathrm{He}+n\mathrm{''}$ ${\mathrm{``}}^{4}\mathrm{He}+n+n\mathrm{''}$ states. From calculated...
We studied the roles of tensor and pairing correlations on halo formation in $^{11}\mathrm{Li}$ with an extended $^{9}\mathrm{Li}+n+n$ model. first solved ground state $^{9}\mathrm{Li}$ shell-model basis by taking 2p-2h states using Gaussian functions variational size parameters to take into account correlation fully. In $^{11}\mathrm{Li}$, are Pauli blocked additional two neutrons, which work coherently make configurations containing $0{p}_{1/2}$-state pushed up close those...
The first conclusive evidence of a dipole resonance in ^{11}Li having isoscalar character observed from inelastic scattering with novel solid deuteron target is reported. experiment was performed at the newly commissioned IRIS facility TRIUMF. results show peak an excitation energy 1.03±0.03 MeV width 0.51±0.11 (FWHM). angular distribution consistent distorted-wave Born approximation framework. together shell model calculations signature that monopole tensor interaction important ^{11}Li. ab...
Abstract The complex scaling method (CSM) is one of the most powerful methods describing resonances with energy eigenstates based on non-Hermitian quantum mechanics. We present basic application CSM to properties unbound phenomena light nuclei. In particular, we focus many-body resonant and non-resonant continuum states observed in unstable also investigate level density (CLD) scattering problem terms Green’s function CSM. discuss explicit effects contributions CLD transition strength functions.
It is shown that the strength function can be expressed as a sum of contributions from bound, resonance and continuum terms role each term investigated complementarily by using complex scaling method (CSM). The mechanism Coulomb breakup reaction of11 Be analyzed, we confirm fact direct but not through resonances. present also applied to other systems its usefulness discussed.
We investigate the role of tensor correlation on structures 4He and its effect doublet splitting in 5He. perform a configuration mixing calculation shell model type bases to represent for 4He. It is found that our describes characteristics correlation, which represented by an admixture 0s1/2 with spatially modified 0p1/2 orbit. For 5He, we solve coupled OCM equation extended 4He+n model, while taking into account cluster. shown produces Pauli blocking, particular, Jπ = 1/2− state, causes...
We investigate the three-body Coulomb breakup of a two-neutron halo nucleus, $^{6}\mathrm{He}$. Based on $\ensuremath{\alpha}+n+n$ model, scattering states $^{6}\mathrm{He}$ are described by using combined methods complex scaling and Lippmann-Schwinger equation. calculate cross section, two-dimensional energy distributions, invariant mass spectra for $E1$ transition discuss relations between structures in these strengths $n$-$n$ $\ensuremath{\alpha}$-$n$ correlations It is found that...
The pion exchange between nucleons generates a strong tensor interaction, which provides large attractive contribution for the binding energy of nucleus. This noncentral interaction is difficult to handle in shell model framework, hinders full understanding nuclear structure. We develop tensor-optimized (TOSM) and now we are able use bare nucleon-nucleon with help unitary correlation operator method (UCOM) short-range hard core. adopt AV8′, calculate explicitly ground state 4He make detailed...
We studied the role of tensor interaction in He isotopes systematically on basis tensor-optimized shell model (TOSM). use a bare nucleon-nucleon AV8${}^{\ensuremath{'}}$ obtained from scattering data. The short-range correlation is treated unitary operator method (UCOM). Using TOSM + UCOM approach, we investigate each spectrum isotopes. It found that enhances $LS$ splitting energy observed ${}^{5}$He, which ${p}_{1/2}$ and ${p}_{3/2}$ orbits play different roles correlation. In...
We develop a new formalism to treat nuclear many-body systems using the bare nucleon–nucleon interaction. It has become evident that tensor interaction plays an important role in due of pion strongly interacting systems. take antisymmetrized molecular dynamics (AMD) as basic framework and add correlation operator acting on AMD wave function concept tensor-optimized shell model. demonstrate systematical straightforward formulation utilizing Gaussian integration differentiation method...
We study the tensor-optimized antisymmetrized molecular dynamics (TOAMD) as a successive variational method in many-body systems with strong interaction for nuclei. In TOAMD, correlation functions tensor force and short-range repulsion their multiples are operated to AMD state wave function. The total function is expressed sum of all components space can be increased successively multiple achieve convergence. All necessary matrix elements operators, consisting Hamiltonian, analytically using...
The generator coordinate method of a microscopic cluster model is developed to treat the resonance and scattering nuclear clusters with complex scaling. We consistently derive formulation scaling for model, in which only relative motions between are transformed wave function. also reveal applicability this Furthermore, we demonstrate framework 2$\alpha$ system $^8$Be obtain solutions non-resonant continuum states. Using these solutions, calculate level density, brings phase shifts...
It is shown that the continuum level density (CLD) at unbound energies can be calculated with complex scaling method (CSM), in which energy spectra of bound states, resonances and states are obtained terms L2 basis functions. In this method, extended completeness relation applied to calculation Green functions, continuum-state part approximately expressed discretized scaled solutions. The result compared CLD exactly from scattering phase shift. discretization CSM give a very good description...
We study the characteristics of tensor correlation in 4He using a shell model type method. treat force explicitly by performing configuration-mixing calculation 2p2h basis and include single-particle states up to intermediately high angular momenta. adopt Gaussian expansion method for quantitative description spatial shrinkage optimize correlation. are able describe full strength realizing convergence. call this tensor-optimized model. It is found that 4He, three specific configurations...
We study the resonance spectroscopy of $^{7}\mathrm{He}$ in $^{4}\mathrm{He}$$+n+n+n$ cluster model, where motion valence neutrons is described orbital shell model. Many-body resonances are treated on correct boundary condition as Gamow states complex scaling method. obtain five and investigate their properties from configurations. In particular, $1/{2}^{\ensuremath{-}}$ state found a low excitation energy 1.1 MeV with width 2.2 MeV, whereas experimental determination position this not so...
We have measured 16O(p,d) reaction using 198-, 295- and 392-MeV proton beams to search for a direct evidence on the effect of tensor interactions in light nucleus. Differential cross sections one-neutron transfer reactions populating ground states several low-lying excited 15O were measured. Comparing ratios each state one over wide range momentum transfer, we found marked enhancement positive-parity state(s). The observation indicates large components high-momentum neutrons initial...
We study the Li isotopes systematically in terms of tensor-optimized shell model (TOSM) by using a bare nucleon-nucleon interaction as AV8' interaction. The short-range correlation is treated unitary operator method (UCOM). Using TOSM+UCOM approach, we investigate role tensor force on each spectrum isotopes. It found that produces quite characteristic effect various states and those spectra are affected considerably force. energy difference between spin-orbit partner, p1/2 p3/2 orbits last...
We investigate the three-body Coulomb breakup of a two-neutron halo nucleus ${}^{11}$Li. use coupled-channel ${}^{9}$Li+$n$+$n$ model, which includes coupling between last neutron states and various two-particle--two-hole ($2\text{p}$-$2\text{h}$) configurations in ${}^{9}$Li due to tensor pairing correlations. The scattering ${}^{11}$Li are described by using combined methods complex scaling Lippmann-Schwinger equation. calculated cross section successfully reproduces experiments. large...