検索対象:     
報告書番号:
※ 半角英数字
 年 ~ 
 年
検索結果: 7 件中 1件目~7件目を表示
  • 1

発表形式

Initialising ...

選択項目を絞り込む

掲載資料名

Initialising ...

発表会議名

Initialising ...

筆頭著者名

Initialising ...

キーワード

Initialising ...

使用言語

Initialising ...

発行年

Initialising ...

開催年

Initialising ...

選択した検索結果をダウンロード

論文

Neutron-hole states in $$^{131}$$Sn and spin-orbit splitting in neutron-rich nuclei

Orlandi, R.; Pain, S. D.*; Ahn, S.*; Jungclaus, A.*; Schmitt, K. T.*; Bardayan, D. W.*; Catford, W. N.*; Chapman, R.*; Chipps, K. A.*; Cizewski, J. A.*; et al.

Physics Letters B, 785, p.615 - 620, 2018/10

 被引用回数:1 パーセンタイル:49.68(Astronomy & Astrophysics)

Low-lying neutron-hole states in $$^{131}$$Sn were populated via the $$^{132}$$Sn(d,t) reaction at Oak Ridge National Laboratory. The triton angular distributions were compared to DWBA calculations and revealed spectroscopic factors compatible with a single-hole nature of the states populated. The data permit to determine the spin-orbit splitting of the strongly bound $$d_{3/2}$$ and $$d_{5/2}$$ neutron orbits below the shell gap, which was compared to the splitting of the weakly bound 3$$p$$ and 2$$f$$ orbits above the gap. The comparison revealed a smaller energy splitting of the 3$$p$$ orbits. All splittings were reproduced using Woods-Saxon calculations, and the lower splitting of the 3$$p$$ orbits was explained to arise from the large radial extent of the wavefunction and small value of the amplitude at the surface. This result is important to understand at a fundamental level the spin-orbit interaction, and its effects on neutron-rich nuclei.

論文

Excitation energy dependence of fragment-mass distributions from fission of $$^{180,190}$$Hg formed in fusion reactions of $$^{36}$$Ar + $$^{144,154}$$Sm

西尾 勝久; Andreyev, A. N.*; Chapman, R.*; Derkx, X.*; D$"u$llmann, C. E.*; Ghys, L.*; He${ss}$berger, F. P.*; 廣瀬 健太郎; 池添 博*; Khuyagbaatar, J.*; et al.

Physics Letters B, 748, p.89 - 94, 2015/09

 被引用回数:9 パーセンタイル:26.51(Astronomy & Astrophysics)

Mass distributions of fission fragments from the compound nuclei $$^{180}$$Hg and $$^{190}$$Hg formed in fusion reactions $$^{36}$$Ar+$$^{144}$$Sm and $$^{36}$$Ar+$$^{154}$$Sm, respectively, were measured at initial excitation energies of $$E^*$$($$^{180}$$Hg)=,33$$-$$66 MeV and $$E^*$$($$^{190}$$Hg)=,48$$-$$71 MeV. In the fission of $$^{180}$$Hg, the mass spectra were well reproduced by assuming only an asymmetric-mass division, with most probable light and heavy fragment masses $$bar{A}_{rm L}$$/$$bar{A}_{rm H}=$$79$$/$$101. The mass asymmetry for $$^{180}$$Hg agrees well with that obtained in the low-energy $$beta^textrm{+}$$/EC-delayed fission of $$^{180}$$Tl, from our earlier ISOLDE(CERN) experiment. Fission of $$^{190}$$Hg is found to proceed in a similar way, delivering the mass asymmetry of $$bar{A}_{rm L}$$/$$bar{A}_{rm H}=$$83$$/$$107, throughout the measured excitation energy range. The persistence as a function of excitation energy of the mass-asymmetric fission for both proton-rich Hg isotopes gives strong evidence for the survival of microscopic effects up to effective excitation energies of compound nuclei as high as 40,MeV. This behavior is different from fission of actinide nuclei and heavier mercury isotope $$^{198}$$Hg.

論文

Single-neutron orbits near $$^{78}$$Ni; Spectroscopy of the N=49 isotope $$^{79}$$Zn

Orlandi, R.; M$"u$cher, D.*; Raabe, R.*; Jungclaus, A.*; Pain, S. D.*; Bildstein, V.*; Chapman, R.*; de Angelis, G.*; Johansen, J. G.*; Van Duppen, P.*; et al.

Physics Letters B, 740, p.298 - 302, 2015/01

 被引用回数:15 パーセンタイル:13.65(Astronomy & Astrophysics)

Single-neutron states in $$^{79}$$Zn have been populated using the reaction $$^{78}$$Zn(d,p) at REX-Isolde, CERN. The analysis reveals that the lowest excited states in $$^{79}$$Zn lie at approximately 1 MeV, and involve neutron orbits above the N=50 shell gap. A 5/2$$^{+}$$ configuration was assigned to the 983-keV state. Comparison with large-scale shell model calculations supports a robust neutron N=50 shell closure for $$^{78}$$Ni. These data constitute an important step towards the understanding the magicity of $$^{78}$$Ni and the structure of nuclei in the region.

論文

An Approximate single fluid 3-dimensional magnetohydrodynamic equilibrium model with toroidal flow

Cooper, W. A.*; Hirshman, S. P.*; Chapman, I. T.*; Brunetti, D.*; Faustin, J. M.*; Graves, J. P.*; Pfefferl$'e$, D.*; Raghunathan, M.*; Sauter, O.*; Tran, T. M.*; et al.

Plasma Physics and Controlled Fusion, 56(9), p.094004_1 - 094004_8, 2014/09

 被引用回数:4 パーセンタイル:67.31(Physics, Fluids & Plasmas)

入れ子の磁気面を持つ一流体三次元MHD平衡にトロイダル回転を適切に考慮するモデルを開発した。このモデルは軸対称系における回転を考慮したMHD平衡を厳密に再現できる。このモデルは三次元的な変化の大きい領域でプラズマ回転のシアが無視できる場合に適用可能である。MAST装置におけるヘリカルコアを持つ平衡において、回転の影響は磁場構造に対しては小さいが圧力分布は大きく変化させることを示した。この圧力の変化は磁気軸付近の圧力の減少であり、回転によってさらなる3次元的な変化を引き起こすものではなかった。

論文

Empirical scaling of sawtooth period for onset of neoclassical tearing modes

Chapman, I. T.*; Buttery, R. J.*; Coda, S.*; Gerhardt, S.*; Graves, J. P.*; Howell, D. F.*; 諫山 明彦; La Haye, R. J.*; Liu, Y.*; Maget, P.*; et al.

Nuclear Fusion, 50(10), p.102001_1 - 102001_7, 2010/10

 被引用回数:36 パーセンタイル:12.27(Physics, Fluids & Plasmas)

本論文では、ASDEX-U, DIII-D, HL-2A, JET, JT-60U, MAST, NSTX, TCV, Tore Supraにおいて鋸歯状振動と新古典テアリングモード(NTM)の発生について調べた結果について記述している。データベース解析の結果、鋸歯状振動がNTMを誘起したときのベータ値は鋸歯状振動の周期とともに低下することがわかった。また、装置間で鋸歯状振動を比較する場合、鋸歯状振動周期を抵抗性拡散時間で規格化し、プラズマ圧力として規格化ベータ値($$beta_N$$)を用いることがよいことがわかった。今回の結果をITERに外挿した場合、鋸歯状振動周期が10秒の場合は$$beta_Nsim 4$$でNTMが誘起されると予想されるのに対し、鋸歯状振動周期が100秒の場合は$$beta_Nsim 2$$でNTMが誘起されると予想されることがわかった。

口頭

Low-energy states in $$^{79}$$Zn and the structure of $$^{78}$$Ni

Orlandi, R.; M$"u$cher, D.*; Raabe, R.*; Jungclaus, A.*; Pain, S. D.*; Bildstein, V.*; Chapman, R.*; de Angelis, G.*; Johansen, J. G.*; Van Duppen, P.*; et al.

no journal, , 

Single-neutron states in the $$N$$ = 49 isotope $$^{79}$$Zn were populated in the $$^{78}$$Zn(d,p)$$^{79}$$Zn transfer reaction at REX-ISOLDE, CERN. The combined detection of protons ejected in the reaction and of $$gamma$$ rays emitted by $$^{79}$$Zn permitted the identification of the lowest-lying 5/2$$^+$$ and 1/2$$^+$$ excited states. The analysis of proton angular distributions links these states to a significant amount of single-particle strength around 1 MeV, and specifically to the $$nu$$d$$_{5/2}$$ and $$nu$$s$$_{1/2}$$ neutron orbits, which lie above the $$N$$ = 50 neutron shell gap. Comparison with large-scale-shell-model calculations supports a robust $$N$$ = 50 shell-closure for $$^{78}$$Ni. These data constitute a considerable step towards the understanding of the magicity of $$^{78}$$Ni and of the structure of isotopes in the region.

口頭

Neutron hole states in $$^{131}$$Sn studied via the $$^{132}$$Sn(d,t)$$^{131}$$Sn reaction

Orlandi, R.; Pain, S. D.*; Bardayan, D. W.*; Gross, C. J.*; Smith, M. S.*; Jungclaus, A.*; Ahn, S.*; Jones, K. L.*; Pittman, S. T.*; Schmitt, K. T.*; et al.

no journal, , 

Knowledge of single-particle energies in the vicinity of exotic doubly-magic nuclei is of critical importance to understand evolution of nuclear structure. In the present work, the $$^{132}$$Sn(d,t)$$^{131}$$Sn reaction (Q=-1.055 MeV) was studied in inverse kinematics at HRIBF of Oak Ridge National Laboratory. The $$^{132}$$Sn ISOL beam was post-accelerated to an energy of 4.39 MeV/u using the ORNL HRIBF accelerator. The beam (average intensity of $$sim$$1.2e4 pps) impinged on a $$sim$$250 $$mu$$g/cm$$^{2}$$ deuterated polyethylene target, for approximately 4 days. Ejected tritons were detected using the Super ORRUBA array of segmented Si telescopes. Low-lying states in $$^{131}$$Sn were populated in the experiment. Preliminary results will be shown.

7 件中 1件目~7件目を表示
  • 1