Project/Area Number 
10440120

Research Category 
GrantinAid for Scientific Research (B).

Allocation Type  Singleyear Grants 
Section  一般 
Research Field 
物理学一般

Research Institution  The University of ElectroCommunications 
Principal Investigator 
MATSUZAWA Michio Faculty of ElectroCommunications, The University of ElectroCommunications, Professor., 電気通信学部, 教授 (10010943)

CoInvestigator(Kenkyūbuntansha) 
MORISHITA Toru Faculty of ElectroComm., The University of ElectroCommunications, Research Associate, 電気通信学部, 助手 (20313405)
HINO Kenichi Inst.of Materials Science, Univ.of Tsukuba, Associate Professor, 物質工学系, 助教授 (90228742)
WATANABE Shinichi Faculty of ElectroComm., The University of ElectroCommunications, Professor, 電気通信学部, 教授 (60210902)

Project Period (FY) 
1998 – 2000

Project Status 
Completed (Fiscal Year 2000)

Budget Amount *help 
¥7,600,000 (Direct Cost: ¥7,600,000)
Fiscal Year 2000: ¥1,900,000 (Direct Cost: ¥1,900,000)
Fiscal Year 1999: ¥2,900,000 (Direct Cost: ¥2,900,000)
Fiscal Year 1998: ¥2,800,000 (Direct Cost: ¥2,800,000)

Keywords  exotic particles / threshold law / ionization / particle correlation / halfcycle pulse / hyperspherical elliptic coordinates / quasiseparability / triply excited states / 起球楕円座標 / イオン化閾則 / 視覚化 / ボーズアインシュタイン凝縮 / 複素断熱ポテンシャル / プロトニウム / イオン化 / 指数関数的閾則 / 半周期パルス / 準安定状態 
Research Abstract 
Employing the approach of hyperspherical coordinates, we investigate particle correlations of novel quantum states of Coulomb threebody system including exotic particles. The hyperspherical approach is based on the adiabatic approximation as hyper radius which measures the size of the systems is treated as an adiabatic parameter. Electron correlation is investigated in the model electronimpact problem in which the target hydrogen atom interacts with the incident electron only by monopole. It is found that the threshold law shows an exponential form related to the local instability of the ridge motion. This approach is also extended to electronimpact ionization of the collinear Z=1/4 model atom. Slightly above the ionization limit, ab initio calculation reveals a distinct dip due to the shortrange dynamics. In the middle of 1990, the hyperspherical elliptic (HSE) coordinates was introduced which is suitable for treating the Coulomb three body systems with arbitrary mass ratios. At first, HSE harmonics are investigated which are the eigenfunctions of the generalized angular operator by separating the variables in the HSE coordinates. This harmonics are related to the Heun equation. An efficient method is developed to construct HSE harmonics for application for the Coulomb three body problems. An approximate symmetry of the Coulomb three body problemis is found which leads to the approximate separability of the hyperspherical adiabatic eigenvalue problem in HSE coordinates and to the set of HSE quantum numbers. This enables us to establish the rapidly convergent expansion of the HSE basis set and to get the highly reliable estimates of the energy levels for Coulomb three body systems. The conventional HS method is also applied to study electron correlation of triply excited states of atoms. Metastability of of atoms under the application of half cycle pulse is also studied based on the model of harmonic oscillator.
