1991 Fiscal Year Annual Research Report

リングサイクロトロンを用いた核構造・核反応の研究

Research Project

Project/Area Number	01302012
Research Institution	Tokyo Institute of Technology
Principal Investigator	大沼甫東京工業大学, 理学部, 教授 (00011544)
Co-Investigator(Kenkyū-buntansha)	森信俊平九州大学, 理学部, 教授 (50016078) 鹿取謙二大阪大学, 理学部, 教授 (20013485) 滝川昇東北大学, 理学部, 助教授 (00125600) 織原彦之丞東北大学, サイクロトロンRIセンター, 教授 (00004432) 谷畑勇夫理化学研究所, リニアック研究室, 主任研究員 (10089873)
Keywords	リング・サイクロトロン / 核構造 / 核反応 / 中性子ハロ- / オンライン質量分析 / 原子核の安定性 / 天体核物理 / スピンアイソスピン励起
Research Abstract	本年度も引続き各サブグ-プにおいて活発な討論と準備が行われた。全ての装置は順調に稼働し、多くの実験デ-タが得られ、その解析・検討と議論が理論研究者も構えて進められている。中性子過剰核については、ハ-トリ-フォック殻模型計算や、相対論的ハ-トリ-理論など多くの理論計算がなされた。これらの核に現れる低い巨大共鳴は引続き理論・実験の両面からの追求がなされている。さらに逆運動学的条件を用いて、中性子過剰核による陽子の弾性散乱が測定された。またこのような中性子過剰核を用いた超重元素合成の可能性なども議論された。また重イオン破砕片の偏極に関する新しいデ-タが得られ、その運動量依存性が簡単な運動学的考察から説明できることが示された。質量分離器GARIS/IGISOLによるレ-ザ-核分光では、これまでどこでも実現していなかった高融点元素ハフニウムの同位体の生成取り出しに成功した。高励起核からの中性子およびガンマ線測定では、原子核を高温にしたときにどこまで原子核として存在し得るか、という問題が引続き追求されている。不安定核のク-ロン励起の実験では、天体核反応・元素合成に関する新しいデ-タが得られた。また磁気スペクトロメ-タ-を用いて(d, ^2He)反応の測定が行われ、この反応のO度での断面積がガモフテラ-強度と比例関係にあり、原子核のスピンアイソスピン励起の研究に対する新しい手段となり得ることが示された。磁気スペクトロメ-タ-とスウィンガ-を用いて同一方向に放出された陽子・中性子を同時に検出し、重陽子の崩壊過程と終状態相互作用に関する知見が得られた。また磁気スペクトロメ-タ-で重イオン荷電交換反応を検出する試みがなされ、O度での検出に成功した。これらの成果は1月27日ー29日に行われた成果発表会・研究会で報告され、延べ180人が出席、活発な議論が取り交わされた。

Research Products

(41 results)

All Other

All Publications (41 results)

[Publications] H.Katsuragawa: "High Density Atomic Beam Source by a Laser Ablation Method" Nucl.Instr.Meth.B43. 259-261 (1989)
[Publications] A.Iwamoto: "Anomalous Enhancement of the SubーBarrier Fusion Cross Section by Cooperative Shell and Deformation Effects" Phys.Lett.B219. 176-180 (1989)
[Publications] H.Toki: "Ikeda's sum rule and chargeーexchange reactions Fe" Phys.Let.B219. 181-183 (1989)
[Publications] E.Uegaki: "On Resonance of the 24Mgー24Mg System" Phys.Lett.B231. 28-34 (1989)
[Publications] T.Kobayashi: "Electromagnetic Dissociation and Soft Giant Dipole Resonance of the NeutronーDripline Nucleus 11Li" Phys.Lett.B232. 51-55 (1989)
[Publications] H.Harada: "HighーSpin states in 114Sn" Phys.Rev.C39. 511-512 (1989)
[Publications] I.Tanihata: "On the possible use of secondary radioactive beams" Tratise on HeavyーIon Science. 8. 443-514 (1989)
[Publications] S.Kubono: "The Proton Threshold States in 21Mg Relevant to the rpーProcess" Z.Phys.A334. 511-512 (1989)
[Publications] H.Toki: "Origin of quenching of GamowーTeller strength in 54Fe" Z.Phys.A334. 523-524 (1989)
[Publications] T.Ichihara: "Data Acquisition System at the RIKEN Accelerator Fecility" IEEE Trans.Nucl.Sc.36. 1628-1629 (1989)
[Publications] W.P.Liu: "Identification of projectile fragments using position sensitive silicon detectors" Nucl.Instr.Meth.A287. 476-480 (1990)
[Publications] T.Nakagawa: "Timing properties of a new type time pickーup detector" Nucl.Instr.Meth.A290. 136-138 (1990)
[Publications] Y.L.Luo: "A semiclassical model for inclusivc nucloon inelastic scattering to continuum" Phys.Lett.B235. 211-214 (1990)
[Publications] K.Asahi: "New aspcet of intermediate energy heavy ion reactions.Largc spin polarization of fragments" Phys.Lett.B251. 488-492 (1990)
[Publications] G.Tatara: "The imaginary port of channelーcoupling potentials for 6Li induced reactions." Prog.Theor.Phys.83. 552-564 (1990)
[Publications] S.Mizutori: "Octuploe vibrations built on superdeformed rotational bands" Prog.Theor.Phys.83. 666-670 (1990)
[Publications] T.Tazawa: "Resonances due to the LandauーZener Transition" Phys.Rev.C41. R17-R20 (1990)
[Publications] K.Asahi: "Halfーlife and branching ratios of 130 beta decay" Phys.Rev.C41. 358-361 (1990)
[Publications] M.Ichimura: "Relation among theories of inclusive breakup reactions" Phys.Rev.C41. 834-840 (1990)
[Publications] N.Takigawa: "Thermal decay rate of multidimensional fission under a nonlinear coupling" Phys.Rev.C41. 2451-2454 (1990)
[Publications] K.Shimoura: "Nuclear polarization and magnetic resonance of unstable 170Tm with betaーray radiationーdetected optical pumping in solids" Phys.Rev.C42. R487-R490 (1990)
[Publications] Y.Hatsukawa: "Systematics of alpha decay halfーlives" Phys.Rev.C42. 674-682 (1990)
[Publications] T.Minamisono: "Electromagnetic moments of the doubly closed she11±1 nucleon nuclei and onーline nuclear polarization" Hyperfine Int.59. 31-40 (1990)
[Publications] H.Nakahara: "Systematic behaviour of mass yield curves in low energy fission of actinides" J.Raioanal.Nucl.Chem.142. 231-251 (1990)
[Publications] K.YuasaーNakagawa: "Properties of the fast timing detector using an electron multiplier" Nucl.Instr.Meth.A300. 538-541 (1991)
[Publications] T.Suzuki: "Negative pion production in subthreshold heavy ion collisions" Phys.Lett.B257. 27-31 (1991)
[Publications] N.Takigawa: "A geometric approach to strong coupling effects in heavyーion collisions" Phys.Lett.B262. 199-204 (1991)
[Publications] T.Motobayashi: "Determination of the astrophysical 13N(p,γ)140 cross section through the Coulomb dissociation method" Phys.Lett.B264. 259-263 (1991)
[Publications] N.Takigawa: "Interaction potential and fusion of a halo nucleus" Phys.Lett.B265. 23-28 (1991)
[Publications] M.Fukuda: "Neutron halo in 11Be studied via reaction cross sections" Phys.Lett.B268. 339-344 (1991)
[Publications] H.Toki: "Properties of nuclei far from the stability line in the relativistic Hartree theory" Nucl.Phys.A524. 633-648 (1991)
[Publications] K.ーI.Kubo: "The spin distribution in heavyーion fusion" Nucl.Phys.A534. 393-402 (1991)
[Publications] T.Tazawa: "Quantumーmechanical study of the LandauーZener resonaces in nuclear heavyーion collisions" Prog.Theor.Phys.85. 567-587 (1991)
[Publications] S.Mizutori: "Soft octupole vibrations with K=0 and K≠0 built on superdeformed rotational bands and static pairing correlations" Prog.Theor.Phys.86. 131-149 (1991)
[Publications] K.Asahi: "Observation of spinーaligned secondary fragment beams of 14B" Phys.Rev.C43. 456-460 (1991)
[Publications] A.B.Balantekin: "Description of nuclear structure effects in subーbarrier fusion by the interacting boson model" Phys.Rev.C44. 145-151 (1991)
[Publications] N.Takigawa: "Dynamic polarization potential induced by the Coulomb excitation of deformed heavy ions" Phys.Rev.C44. 477-484 (1991)
[Publications] K.Heiguchi: "Halfーlives and Qβ measurements for new nuclei of 89Tc and 89mTc" Z.Phys.A338. 7-10 (1991)
[Publications] M.Koizumi: "Velocity distribution of ion beams from the RIKEN IGISOL" Nucl.Instr.Meth.
[Publications] Y.Fukashiro: "Nuclear laser spectroscopy using a laser microwave double resonance" Hyperfine lnt.
[Publications] M.Koizumi: "Collinear fast atomic beam laser spectroscopy at RIKEN GARIS/IGISOL" Hyperfine Int.

1991 Fiscal Year Annual Research Report

リングサイクロトロンを用いた核構造・核反応の研究

Principal Investigator

大沼 甫 東京工業大学, 理学部, 教授 (00011544)

Research Products

[Publications] H.Katsuragawa: "High Density Atomic Beam Source by a Laser Ablation Method" Nucl.Instr.Meth.B43. 259-261 (1989)

[Publications] A.Iwamoto: "Anomalous Enhancement of the SubーBarrier Fusion Cross Section by Cooperative Shell and Deformation Effects" Phys.Lett.B219. 176-180 (1989)

[Publications] H.Toki: "Ikeda's sum rule and chargeーexchange reactions Fe" Phys.Let.B219. 181-183 (1989)

[Publications] E.Uegaki: "On Resonance of the 24Mgー24Mg System" Phys.Lett.B231. 28-34 (1989)

[Publications] T.Kobayashi: "Electromagnetic Dissociation and Soft Giant Dipole Resonance of the NeutronーDripline Nucleus 11Li" Phys.Lett.B232. 51-55 (1989)

[Publications] H.Harada: "HighーSpin states in 114Sn" Phys.Rev.C39. 511-512 (1989)

[Publications] I.Tanihata: "On the possible use of secondary radioactive beams" Tratise on HeavyーIon Science. 8. 443-514 (1989)

[Publications] S.Kubono: "The Proton Threshold States in 21Mg Relevant to the rpーProcess" Z.Phys.A334. 511-512 (1989)

[Publications] H.Toki: "Origin of quenching of GamowーTeller strength in 54Fe" Z.Phys.A334. 523-524 (1989)

[Publications] T.Ichihara: "Data Acquisition System at the RIKEN Accelerator Fecility" IEEE Trans.Nucl.Sc.36. 1628-1629 (1989)

[Publications] W.P.Liu: "Identification of projectile fragments using position sensitive silicon detectors" Nucl.Instr.Meth.A287. 476-480 (1990)

[Publications] T.Nakagawa: "Timing properties of a new type time pickーup detector" Nucl.Instr.Meth.A290. 136-138 (1990)

[Publications] Y.L.Luo: "A semiclassical model for inclusivc nucloon inelastic scattering to continuum" Phys.Lett.B235. 211-214 (1990)

[Publications] K.Asahi: "New aspcet of intermediate energy heavy ion reactions.Largc spin polarization of fragments" Phys.Lett.B251. 488-492 (1990)

[Publications] G.Tatara: "The imaginary port of channelーcoupling potentials for 6Li induced reactions." Prog.Theor.Phys.83. 552-564 (1990)

[Publications] S.Mizutori: "Octuploe vibrations built on superdeformed rotational bands" Prog.Theor.Phys.83. 666-670 (1990)

[Publications] T.Tazawa: "Resonances due to the LandauーZener Transition" Phys.Rev.C41. R17-R20 (1990)

[Publications] K.Asahi: "Halfーlife and branching ratios of 130 beta decay" Phys.Rev.C41. 358-361 (1990)

[Publications] M.Ichimura: "Relation among theories of inclusive breakup reactions" Phys.Rev.C41. 834-840 (1990)

[Publications] N.Takigawa: "Thermal decay rate of multidimensional fission under a nonlinear coupling" Phys.Rev.C41. 2451-2454 (1990)

[Publications] K.Shimoura: "Nuclear polarization and magnetic resonance of unstable 170Tm with betaーray radiationーdetected optical pumping in solids" Phys.Rev.C42. R487-R490 (1990)

[Publications] Y.Hatsukawa: "Systematics of alpha decay halfーlives" Phys.Rev.C42. 674-682 (1990)

[Publications] T.Minamisono: "Electromagnetic moments of the doubly closed she11±1 nucleon nuclei and onーline nuclear polarization" Hyperfine Int.59. 31-40 (1990)

[Publications] H.Nakahara: "Systematic behaviour of mass yield curves in low energy fission of actinides" J.Raioanal.Nucl.Chem.142. 231-251 (1990)

[Publications] K.YuasaーNakagawa: "Properties of the fast timing detector using an electron multiplier" Nucl.Instr.Meth.A300. 538-541 (1991)

[Publications] T.Suzuki: "Negative pion production in subthreshold heavy ion collisions" Phys.Lett.B257. 27-31 (1991)

[Publications] N.Takigawa: "A geometric approach to strong coupling effects in heavyーion collisions" Phys.Lett.B262. 199-204 (1991)

[Publications] T.Motobayashi: "Determination of the astrophysical 13N(p,γ)140 cross section through the Coulomb dissociation method" Phys.Lett.B264. 259-263 (1991)

[Publications] N.Takigawa: "Interaction potential and fusion of a halo nucleus" Phys.Lett.B265. 23-28 (1991)

[Publications] M.Fukuda: "Neutron halo in 11Be studied via reaction cross sections" Phys.Lett.B268. 339-344 (1991)

[Publications] H.Toki: "Properties of nuclei far from the stability line in the relativistic Hartree theory" Nucl.Phys.A524. 633-648 (1991)

[Publications] K.ーI.Kubo: "The spin distribution in heavyーion fusion" Nucl.Phys.A534. 393-402 (1991)

[Publications] T.Tazawa: "Quantumーmechanical study of the LandauーZener resonaces in nuclear heavyーion collisions" Prog.Theor.Phys.85. 567-587 (1991)

[Publications] S.Mizutori: "Soft octupole vibrations with K=0 and K≠0 built on superdeformed rotational bands and static pairing correlations" Prog.Theor.Phys.86. 131-149 (1991)

[Publications] K.Asahi: "Observation of spinーaligned secondary fragment beams of 14B" Phys.Rev.C43. 456-460 (1991)

[Publications] A.B.Balantekin: "Description of nuclear structure effects in subーbarrier fusion by the interacting boson model" Phys.Rev.C44. 145-151 (1991)

[Publications] N.Takigawa: "Dynamic polarization potential induced by the Coulomb excitation of deformed heavy ions" Phys.Rev.C44. 477-484 (1991)

[Publications] K.Heiguchi: "Halfーlives and Qβ measurements for new nuclei of 89Tc and 89mTc" Z.Phys.A338. 7-10 (1991)

[Publications] M.Koizumi: "Velocity distribution of ion beams from the RIKEN IGISOL" Nucl.Instr.Meth.

[Publications] Y.Fukashiro: "Nuclear laser spectroscopy using a laser microwave double resonance" Hyperfine lnt.

[Publications] M.Koizumi: "Collinear fast atomic beam laser spectroscopy at RIKEN GARIS/IGISOL" Hyperfine Int.

大沼甫東京工業大学, 理学部, 教授 (00011544)