Hiroshi Masui

Partial Decay Widths in Coupled-Channel Systems with the Complex-Scaled Jost Function Method

Partial decay widths of resonant states in a coupled-channel system are studied by using the complex-scaled Jost function method (CSJFM). With CSJFM, we use the ratio of the S-matrices to calculate partial decay widths, and then we need not introduce any “channel radius”, which is used in standard scattering theory. Combining the Jost function method (JFM) and the complex scaling method (CSM), we can easily obtain many resonant states even for a large total width and partial decay widths simultaneously. Several methods to calculate partial decay widths in CSM are also discussed and are shown to give the same values in CSJFM.

Study of virtual states in 5He and 10Li with the Jost function method

Abstract We study virtual states in 5 He and 10 Li by using the Jost function method (JFM). In 5 He, we obtained an s -wave pole with the complex energy E=7.50−44.7 i MeV using a 4 He–n potential called KKNN. In 10 Li, we investigated s -wave virtual poles with the 9 Li–n interaction microscopically constructed by taking into account the Pauli-blocking effect. We obtained a virtual state at E=−0.135 MeV ( k=−0.077 i fm −1 ). The attractive property of the s -wave 9 Li–n potential for 10 Li is discussed in comparison with the 5 He ( 4 He + n) system and also calculational results for the 9 Li–n potential of Thompson and Zhukov.

Study of Resonance States in a Coupled-Channel System with the Jost Function Method Applying the Orthogonality Condition Model

To study resonant and virtual states in a wide variety of nuclear systems, we develop the Jost function method (JFM) for treating systems having non-local potentials. In the case that the Pauli principle for nucleons between clusters is treated by applying the orthogonality condition model (OCM) to the JFM, the pseudo-potential of the OCM can be considered one of the non-local potentials. As examples to demonstrate the applicability of our method, we apply it to a 1 6 O+α single-channel system and also a 9 Li+n coupled-channel system. We also treat a 1 6 O+n single-channel system with a knock-on exchange kernel to confirm that our method is applicable in more general cases having non-local potentials.

Development of a charged-particle nuclear reaction data retrieval system on Intelligent Pad: CONTIP

A newly designed retrieval system of charged-particle nuclear reaction data (CPND) is developed on the IntelligentPad architecture. NRDF (Nuclear Reaction Data File), which is a kind of CPND compilation, is applied as an example. The authors designed the network-based (client-server) retrieval system. The server system is constructed on a UNIX workstation with a relational database; the client system is built on a Microsoft Windows PC using an IntelligentPad software package. The system is called CONTIP, which is an abbreviation of ‘Creative, Cooperative and Cultural Objects for Nuclear data and Tools on IntelligentPad’. CONTIP will be developed to realise effective utilisation of nuclear reaction data: (i) reproduction, re-edit, reuse, (ii) circulation, coordination and evolution and (iii) knowledge discovery.

Coupled-channel study for O-isotopes with the core plus valence neutrons model

Abstract We study 17 O and 18 O nuclei by using the core+ n (+ n ) model. We perform the coupled-channel and the resonating group method (RGM) calculations not only for bound states but also for resonant states of 17 O. We obtain the state independent core- n interaction, which includes the exchange kernel, and reasonable single-particle energy (SPE) in the 16 O core. By using the same interaction mechanism of 17 O, we study 18 O in the core+ n + n system.

Study of the s-wave properties in the 9Li-n system with the Jost function method

We study the properties of s-wave potential of 9Li-n by applying the microscopically derived potential model. In this work, we investigate the s-wave virtual state in terms of the cross-section.

COUPLED-CHANNEL STUDY FOR O-ISOTOPES WITH THE CORE PLUS VALENCE NEUTRONS MODEL

We study 17O and 18O nuclei by using the core+n(+n) model. We perform the coupled-channel and the resonating group method (RGM) calculations not only for bound states but also for resonant states of 17O. We obtain the state dependent core-n folding potential and reasonable single-particle energy (SPE) in the 16O core. By using the same interaction for 17O, we study 18O in the core+n+n system.

Exploratory Study of Nuclear Reaction Data Utility Framework of Japan Charged Particle Reaction Data Group (JCPRG)

Compilation, evaluation and dissemination are essential pieces of work for the nuclear data activities. We, Japan charged particle data group, have researched the utility framework for the nuclear reaction data on the basis of recent progress of computer and network technologies. These technologies will be not only for the data dissemination but for the compilation and evaluation assistance among the many corresponding researchers of all over the world. In this paper, current progress of our research and development is shown.

Coupled‐channel study for O‐isotopes with the core plus valence neutrons model

We study the 17O by using the core+n model. As a new approach, we perform the coupled‐channel and RGM calculation not only for bound states but also resonant states of 17O. We obtain the state dependent core‐n folding potential and reasonable SPE in the 16O core.

Complex Scaling Methods for the Study of Light Unstable Nuclei

We point out that the complex scaling method is one of the most successful framework to study many-body resonances. As recent developments of the complex scaling method, we present several ways to analyze the properties of resonant states; the matrix elements associated with resonant states, the extended completeness relation and partial widths of resonances. We also discuss the binding mechanism and excited resonant structure of the Borromean systems: 4He+n+n and 9Li+n+n. We show that the pairing correlation between valence neutrons and between core neutrons plays an important role in neutron-rich nuclei.