1997 Fiscal Year Annual Research Report

ストレンジネス原子核の理論的研究

Research Project

Project/Area Number	08239104
Research Institution	Osaka Electro-Communication University
Principal Investigator	元場俊雄大阪電気通信大学, 工学部, 教授 (90121863)
Co-Investigator(Kenkyū-buntansha)	糸永一憲宮崎医科大学, 医学部, 教授 (90029546) 山本安夫都留文化大学, 文学部, 教授 (80124866) 岡真東京工業大学, 理学部, 教授 (60144606) 矢崎紘一東京大学, 大学院・理学系, 教授 (60012382) 赤石義紀高エネルギー加速器研究機構, 素核研, 教授 (50001839)
Keywords	ハイパー原子核 / ハイパロン核子相互作用 / パイ中間子型弱崩壊 / 非中間子型弱崩壊 / ストレンジネス・ハロ- / ハイパー核寿命 / ダブルハイパー核
Research Abstract	主な成果や進展等の状況を簡潔にまとめる:(1)軽いΛハイパー核構造の精密な計算により,LS力やodd成分やσ_Λ・σ_Ν成分の役割が明らかにされ,p殻領域と比較検討可能となった.また一連の解析を通じて^4_ΣHeの束縛状態の存在を確証する上で大きな貢献をした.(2)^7Liおよび^9Beを標的とした(K^-,K^+)反応でできるΞ状態からダブルハイパー核生成に至る詳細な計算が行われ,特定のΛΛ核や励起状態の生成率が大きいなど,それぞれ注目すべき結果を得た.また準弾性のΞを経由するΛΛ核生成のシナリオが提出された.(3)中間子交換とquark交換によるYN,YY相互作用については,特にLS力の定量的役割あるいは反対称LS力の効き方とSU(3)の破れの効果等が明らかにされた.中間子交換模型による新しい試みとそれらの異同についても検討が進んでいる.またHNおよびHH相互作用のquark模型による計算で斥力引力効果を調べた.(4)非中間子型弱崩壊については,4体quark弱相互作用に基づく直接過程のΔI=3/2遷移の重要な役割が指摘され,また1π,2π交換の役割と効果についても解析が進んだ.ΛΛ核のπ中間子型崩壊の一連の予測がなされた.(5)シミュレーション計算の手法を静止K^-吸収や静止Ξ^-吸収あるいは(K^-,K^+)反応に適用して,hyperfragments生成に関与するクラスター相関や各種2段階過程の分析が進んだ.(6)K^-やΞ^-原子過程の詳細な解析がなされた.

Research Products
(20 results)

All Other

All Publications (20 results)

[Publications] E,Hiyama, et al.: "Three- and Four-Body Cluster Models of Hypernuclei Using the G-Matrix ΛN Interaction" Progress of Theoretical Physics. 97. 881-899 (1997)
[Publications] Y.Yamamoto, et al.: "Production of Double-Λ Hypernuclei at(K^-,K^+)Reaction Points and Their Pionic Decays" Nuclear Physics A. 625. 107-142 (1997)
[Publications] R.H.Dalitz, et al.: "Proton Emitting Λ-Bound States of ^<16>_Λ^<O*>" Nuclear Physics A. 625. 71-94 (1997)
[Publications] T.Motoba: "Pionic Weak Decays of Double-Λ Hypernuclei Produced at(K^-,K^+)Reaction Points" Advances in Nuclear Physics and Related Areas. (in press). (1997)
[Publications] K.Itonaga, et al.: "Nonmesonic Decay Rates and Lifetimes of Light-to-Medium Λ-Hypernuclei" Genshikaku Kenkyu. 41. 93-96 (1997)
[Publications] I.T.Obukhovsky, et al.: "Pionic decay of a possible d' dibaryon and the short-range NN interaction" Physical Review C. 56. 3295-3306 (1997)
[Publications] Y.Nara, et al.: "Study of(K^-,K^+)Reactions with in the Quantum Molecular Dynamics Approach" Proc. 25th INS Intern.Symposium on Nuclear and Particle Physics with High-intensity Proton Accelerators,Tokyo. (印刷中). (1996)
[Publications] A.Onishi, et al.: "Quantum Fluctuation Effects on Nuclear and Atomic Cluster Formation" Nucl.Phys.A. (印刷中). (1997)
[Publications] T.Harada, et al.: "Theoretical Analysis of the ^4He(K^-,π^±)Spectrum" Nucl.Phys.A. (印刷中). (1998)
[Publications] T.Harada: "Sigma-Hypernuclei" Proc. of 1st Sino-Japan Symposium on HADRONS AND NUCLEI WITH STRANGENESS,Beijing. (印刷中). (1997)
[Publications] Y.Hirata, et al.: "Formation of twin and double hypernuclei from Ξ^- absorption at rest on ^<12>C" Nucl.Phys.A. (印刷中). (1998)
[Publications] T.Harada: "Strangeness exchange reactions on a helium target" Nucl.Phys.A. (印刷中). (1998)
[Publications] K.Saito, et al.: "Exchange Currents for Hypernuclear Magnetic Moments" Nuclear Physics A. 625. 95-106 (1997)
[Publications] T.Inoue, et al.: "Non-mesonic Weak Decays of Light Hypernuclei in the Direct Quark and One Pion Exchange Mechanisms" Nuclear Physics A. (印刷中). (1998)
[Publications] M.Oka: "Direct Quark Mechanism for Weak ΛN to NN Processes" Nuclear Physics A. (印刷中). (1998)
[Publications] T.Yamada, et al.: "Double-Λ Hypernuclear Productions via Ξ^- Hypernuclear Sates in the ^9Be(K^-,K^+)^9_ΞHe Reaction" Genshikaku Kenkyu. 41. 81-97 (1997)
[Publications] T.Ueda, et al.: "ΛN and ΛΛ interactions in an OBE model and hypernuclei" Genshikaku Kenkyu. 41. 119-125 (1997)
[Publications] T.Yamada, et al.: "Double-Λ,twin-Λ and single-Λ hypernuclear productions for stopped Ξ^- particles in ^<12>C" Physical Review C. 56. 3216-3230 (1997)
[Publications] T.Sakai, et al.: "The interaction between H-dibaryons" Nuclear Physics A. 625. 192-206 (1997)
[Publications] T.Iwama, et al.: "Nuclear transparency in a relativistic quark model" Nucl.Phys.A. 627. 620-644 (1997)

1997 Fiscal Year Annual Research Report

ストレンジネス原子核の理論的研究

Principal Investigator

元場 俊雄 大阪電気通信大学, 工学部, 教授 (90121863)

Research Products

[Publications] E,Hiyama, et al.: "Three- and Four-Body Cluster Models of Hypernuclei Using the G-Matrix ΛN Interaction" Progress of Theoretical Physics. 97. 881-899 (1997)

[Publications] Y.Yamamoto, et al.: "Production of Double-Λ Hypernuclei at(K^-,K^+)Reaction Points and Their Pionic Decays" Nuclear Physics A. 625. 107-142 (1997)

[Publications] R.H.Dalitz, et al.: "Proton Emitting Λ-Bound States of ^<16>_Λ^<O*>" Nuclear Physics A. 625. 71-94 (1997)

[Publications] T.Motoba: "Pionic Weak Decays of Double-Λ Hypernuclei Produced at(K^-,K^+)Reaction Points" Advances in Nuclear Physics and Related Areas. (in press). (1997)

[Publications] K.Itonaga, et al.: "Nonmesonic Decay Rates and Lifetimes of Light-to-Medium Λ-Hypernuclei" Genshikaku Kenkyu. 41. 93-96 (1997)

[Publications] I.T.Obukhovsky, et al.: "Pionic decay of a possible d' dibaryon and the short-range NN interaction" Physical Review C. 56. 3295-3306 (1997)

[Publications] Y.Nara, et al.: "Study of(K^-,K^+)Reactions with in the Quantum Molecular Dynamics Approach" Proc. 25th INS Intern.Symposium on Nuclear and Particle Physics with High-intensity Proton Accelerators,Tokyo. (印刷中). (1996)

[Publications] A.Onishi, et al.: "Quantum Fluctuation Effects on Nuclear and Atomic Cluster Formation" Nucl.Phys.A. (印刷中). (1997)

[Publications] T.Harada, et al.: "Theoretical Analysis of the ^4He(K^-,π^±)Spectrum" Nucl.Phys.A. (印刷中). (1998)

[Publications] T.Harada: "Sigma-Hypernuclei" Proc. of 1st Sino-Japan Symposium on HADRONS AND NUCLEI WITH STRANGENESS,Beijing. (印刷中). (1997)

[Publications] Y.Hirata, et al.: "Formation of twin and double hypernuclei from Ξ^- absorption at rest on ^<12>C" Nucl.Phys.A. (印刷中). (1998)

[Publications] T.Harada: "Strangeness exchange reactions on a helium target" Nucl.Phys.A. (印刷中). (1998)

[Publications] K.Saito, et al.: "Exchange Currents for Hypernuclear Magnetic Moments" Nuclear Physics A. 625. 95-106 (1997)

[Publications] T.Inoue, et al.: "Non-mesonic Weak Decays of Light Hypernuclei in the Direct Quark and One Pion Exchange Mechanisms" Nuclear Physics A. (印刷中). (1998)

[Publications] M.Oka: "Direct Quark Mechanism for Weak ΛN to NN Processes" Nuclear Physics A. (印刷中). (1998)

[Publications] T.Yamada, et al.: "Double-Λ Hypernuclear Productions via Ξ^- Hypernuclear Sates in the ^9Be(K^-,K^+)^9_ΞHe Reaction" Genshikaku Kenkyu. 41. 81-97 (1997)

[Publications] T.Ueda, et al.: "ΛN and ΛΛ interactions in an OBE model and hypernuclei" Genshikaku Kenkyu. 41. 119-125 (1997)

[Publications] T.Yamada, et al.: "Double-Λ,twin-Λ and single-Λ hypernuclear productions for stopped Ξ^- particles in ^<12>C" Physical Review C. 56. 3216-3230 (1997)

[Publications] T.Sakai, et al.: "The interaction between H-dibaryons" Nuclear Physics A. 625. 192-206 (1997)

[Publications] T.Iwama, et al.: "Nuclear transparency in a relativistic quark model" Nucl.Phys.A. 627. 620-644 (1997)

元場俊雄大阪電気通信大学, 工学部, 教授 (90121863)