2003 Fiscal Year Annual Research Report

原子BECおよび希薄量子気体における準保存量の探究

Research Project

Project/Area Number	15540381
Research Institution	The University of Electro-Communications
Principal Investigator	渡邊信一電気通信大学, 電気通信学部, 教授 (60210902)
Co-Investigator(Kenkyū-buntansha)	森下亨電気通信大学, 電気通信学部, 助手 (20313405) 大槻一雅電気通信大学, 電気通信学部, 助手 (80221828)
Keywords	BEC / 超球座標法 / イオン移動度 / 時間発展シミュレーション / 断熱近似
Research Abstract	【渡辺】超球座標法を用いてBECの集団励起と素励起の研究を行い、Gaussian変分法との類似点と差異を明らかにした。また、引力型BECの崩壊に超球座標法を適用して、崩壊開始時間と崩壊後の残留粒子数について調べた。 Tolstikhin博士と共同で、BECの分割を伴う輸送問題の理解のための座標変換理論の構築を始めた。同時にTolstikhin博士は森下の開発したシミュレーションコード(後述)を用いて、輸送問題への応用の準備を始めた。【大槻】移動管を用いるとイオンと原子あるいは分子間との0.1eV以下での衝突実験が行なえる。外部電場Eとイオンの平均速度vを結びつける比例係数を移動度K_0と呼び、点電荷ではE→0の極限で分極極限値K_<pol>に近付くことが知られている。しかし、分子イオンの場合、Heガス中でK_<pol>に漸近したのはN_2^+のみで、他は電場の弱い領域でK_<pol>を下回った。この移動度低下の機構を調べるために、N_2^+、O_2^+について古典軌道計算を行い、運動量移行断面積から移動度を求めた。得られた移動度は実験値をよく再現することから、ポテンシャルの異方性に依存することが明らかになった。【森下】原子内の電子の全てが励起軌道に押し上げられ、内側の殻が空孔になって膨らんだ、中空原子の構造と生成崩壊のダイナミクスの理論的研究を行ってきたが、それらの原子種とイオンの衝突を計算するために開発してきたコンピュータ・コードは、時間に依存する外場中での多電子相関を記述できる高効率性と安定性がある。そのコードの整備と関連の研究を行なった。整備したコードは、BECが時間に依存したトラップに捕らえられて時間発展する様子の記述への拡張に適しており、3次元BEC用計算コードの雛型として、量子渦などの生成の様子を調べるまでに至った。

Research Products

(14 results)

All Other

All Publications (14 results)

[Publications] Koudai Toyota, Shinichi Watanabe: "Two-channel Siegert pseudostate approach to a three-body Coulomb problem : S-wave resonances of Ps-(N=2,3)"Phys.Rev.A. 68. 062504 (2003)
[Publications] M.Zamkov,.E.P.Benis, C.D.Lin, T.G.Lee, T.Morishita, P.Richard, T.J.M Zouros: "Experimental observation and theoretical calculations of triply excited 2s2p^2 ^2S^e,^<2,4>P^e,^2D^e,2p^3 ^2P^0,^2D^0 states of fluorine"Phys.Rev.A. 67. 050703 (2003)
[Publications] T.Morishita, T.Sasajima, S.Watanabe, M.Matsuzawa: "Double ionization of He by fast proton and antiproton impact"Nucl.Last.Method B. 214. 144 (2004)
[Publications] T.Morishita, C.D.Lin: "Hyperspherical Analysis of Multiply Excited States of Atoms"Correlation and polarization in photonic, electronic, and atomic collisions (AIP Conference Proceedings). 697. 165 (2003)
[Publications] C.-N.Liu, A.-T.Le, T.Morishita, B.D.Esry, C.D.Lin: "Hyperspherical Close Coupling Calculations for Charge Transfer Cross Sections in He^<2+>+H(1s) Collisions at Low Energies"23 rd International conference of the Photonic, Electronic and Atomic Collisions, Program with abstracts. We152 (2003)
[Publications] T.Morishita, C.D.Lin: "HYPERSPHERICAL METHOD FOR FOUR-ELECTRON ATOMIC SYSTEMS"23 rd International conference of the Photonic, Electronic and Atomic Collisions, Program with abstracts. We207 (2003)
[Publications] T.Morishita, C.D.Lin: "Radial and Angular Correlations and the Classifications of intershell triply excited states"23 rd International conference of the Photonic, Electronic and Atomic Collisions, Program with abstracts. We214 (2003)
[Publications] T.Morishita, T.Sasajima, S.Watanabe, M.Matsuzawa: "DOUBLE IONIZATION OF HE BY FAST PROTON AND ANTIPROT ON IMPACT USING HYPERSPHERICAL L^2-INTEGRABLE BASIS METHOD"23 rd International conference of the Photonic, Electronic and Atomic Collisions, Program with abstracts. Tu089 (2003)
[Publications] T.Morishita, C.DLin: "Hyperspherical approach to four-electron atomic systems"35 th Conference of the European Group for Atomic Spectroscopy, Abstracs (European conference abstracts). 27B. 123 (2003)
[Publications] T.Sasajima, T.Morishita, S.Watanabe, M.Matsuzawa: "HSL2 method for double ionization of He by fast proton and antiproton impact"Atomic Collision Research in Japan. 29. 34 (2003)
[Publications] H.Ishimura, D.Kushibe, V.N.Ostrovsky, S.Watanabe, M.Matsuzawa: "DECAY PROCESS OF AN ATTRACTIVE BOSE-EINSTEIN CONDENSATE IN HYPERSPHERICAL COORDINATES"Atomic Collision Research in Japan. 29. 59 (2003)
[Publications] M.Mutou, S.Watanabe, M.Matsuzawa: "EXTENSION OF HYPERSPHERICAL METHOD TO ATTRACTIVE TWO-COMPONENT BOSE-EINSTEIN CONDENSATES"Atomic Collision Research in Japan. 29. 63 (2003)
[Publications] K.Toyota, S.Watanabe: "TWO-CHANNEL SIEGERT PSEUDO STATE FORMULATION FOR S-WAVE RESONANCES IN COULOMB THREE-BODY PROBLEM"Atomic Collision Research in Japan. 29. 71 (2003)
[Publications] T.Morishita, C.D.Lin: "Electron Correlations in Atoms : Hyperspherical approach to Multiply Excited Atoms.A chapter in "A garden of Quanta""World Scientific Co.Pte.Ltd.. 502 (2003)

2003 Fiscal Year Annual Research Report

原子BECおよび希薄量子気体における準保存量の探究

Principal Investigator

渡邊 信一 電気通信大学, 電気通信学部, 教授 (60210902)

Research Products

[Publications] Koudai Toyota, Shinichi Watanabe: "Two-channel Siegert pseudostate approach to a three-body Coulomb problem : S-wave resonances of Ps-(N=2,3)"Phys.Rev.A. 68. 062504 (2003)

[Publications] M.Zamkov,.E.P.Benis, C.D.Lin, T.G.Lee, T.Morishita, P.Richard, T.J.M Zouros: "Experimental observation and theoretical calculations of triply excited 2s2p^2 ^2S^e,^<2,4>P^e,^2D^e,2p^3 ^2P^0,^2D^0 states of fluorine"Phys.Rev.A. 67. 050703 (2003)

[Publications] T.Morishita, T.Sasajima, S.Watanabe, M.Matsuzawa: "Double ionization of He by fast proton and antiproton impact"Nucl.Last.Method B. 214. 144 (2004)

[Publications] T.Morishita, C.D.Lin: "Hyperspherical Analysis of Multiply Excited States of Atoms"Correlation and polarization in photonic, electronic, and atomic collisions (AIP Conference Proceedings). 697. 165 (2003)

[Publications] T.Morishita, C.D.Lin: "HYPERSPHERICAL METHOD FOR FOUR-ELECTRON ATOMIC SYSTEMS"23 rd International conference of the Photonic, Electronic and Atomic Collisions, Program with abstracts. We207 (2003)

[Publications] T.Morishita, C.D.Lin: "Radial and Angular Correlations and the Classifications of intershell triply excited states"23 rd International conference of the Photonic, Electronic and Atomic Collisions, Program with abstracts. We214 (2003)

[Publications] T.Morishita, T.Sasajima, S.Watanabe, M.Matsuzawa: "DOUBLE IONIZATION OF HE BY FAST PROTON AND ANTIPROT ON IMPACT USING HYPERSPHERICAL L^2-INTEGRABLE BASIS METHOD"23 rd International conference of the Photonic, Electronic and Atomic Collisions, Program with abstracts. Tu089 (2003)

[Publications] T.Morishita, C.DLin: "Hyperspherical approach to four-electron atomic systems"35 th Conference of the European Group for Atomic Spectroscopy, Abstracs (European conference abstracts). 27B. 123 (2003)

[Publications] T.Sasajima, T.Morishita, S.Watanabe, M.Matsuzawa: "HSL2 method for double ionization of He by fast proton and antiproton impact"Atomic Collision Research in Japan. 29. 34 (2003)

[Publications] H.Ishimura, D.Kushibe, V.N.Ostrovsky, S.Watanabe, M.Matsuzawa: "DECAY PROCESS OF AN ATTRACTIVE BOSE-EINSTEIN CONDENSATE IN HYPERSPHERICAL COORDINATES"Atomic Collision Research in Japan. 29. 59 (2003)

[Publications] M.Mutou, S.Watanabe, M.Matsuzawa: "EXTENSION OF HYPERSPHERICAL METHOD TO ATTRACTIVE TWO-COMPONENT BOSE-EINSTEIN CONDENSATES"Atomic Collision Research in Japan. 29. 63 (2003)

[Publications] K.Toyota, S.Watanabe: "TWO-CHANNEL SIEGERT PSEUDO STATE FORMULATION FOR S-WAVE RESONANCES IN COULOMB THREE-BODY PROBLEM"Atomic Collision Research in Japan. 29. 71 (2003)

[Publications] T.Morishita, C.D.Lin: "Electron Correlations in Atoms : Hyperspherical approach to Multiply Excited Atoms.A chapter in "A garden of Quanta""World Scientific Co.Pte.Ltd.. 502 (2003)

渡邊信一電気通信大学, 電気通信学部, 教授 (60210902)