1 / 49

A=130 区核高自旋态及形状驱动效应研究

第十次全国核结构讨论会. A=130 区核高自旋态及形状驱动效应研究. 朱胜江 , 肖树东 , 甘翠云 , 禹英男 , 许瑞清 , 车兴来 , 李明亮 清华大学物理系 北京 100084 温书贤 , 祝礼华 , 吴晓光 , 李广生 中国原子能科学院 , 北京 102413. With the right tools Nuclear Physics is poised to make significant discoveries that will also impact other fields.

jariah
Download Presentation

A=130 区核高自旋态及形状驱动效应研究

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. 第十次全国核结构讨论会 A=130区核高自旋态及形状驱动效应研究 朱胜江, 肖树东, 甘翠云, 禹英男, 许瑞清, 车兴来, 李明亮 清华大学物理系 北京 100084 温书贤, 祝礼华, 吴晓光, 李广生 中国原子能科学院, 北京 102413

  2. With the right tools Nuclear Physics is poised to make significant discoveries that will also impact other fields • Nuclear Physics is the study of: • Nucleons and atomic nuclei as complex, many body system of quarks or neutrons and protons • Bound together by fundamental forces (Quantum Chromo-Dynamics (QCD), nucleon-nucleon force (NN)) • Deep connection with evolution of the universe - production of the chemical elements – stars, supernovae, etc. Rare Isotope Accelerator (RIA)  CEBAF 12 GeV Upgrade  RHIC upgrade (RHIC II)  RIA CEBAF electrons RHIC protons Tests of Standard Model Underground Experiments Cold Neutron Experiments

  3. A=130区缺中子核的一些核高自旋态研究 形状驱动效应:Xe,Cs,Ba,La,Ce, Pr,Nd等 长椭形变、扁椭形变及形状共存. Chiral doublet bands. 122Cs ---- Chiral doublet bands? 134Ce -----形状共存, 136La -----扁椭形变带。

  4. 实验在中国原子能科学院H-13串列加速器 上进行的. 122Cs, 134Ce, 136La. 标准的在束谱技术: 重离子熔合-蒸发反应, - 符合在线测量与离线数据分析, 激发函数、DCO, 能量与效率刻度等。

  5. I. A＝130区核： 122Cs，研究chiral doublet bands?

  6. Chiral Symmetry(breaking) in Nuclei Spontaneous chiral symmetry breaking can occur in triaxial doubly odd nuclei when there are three mutually perpendicularspin vectors of differing lengths that can form a left-handed or right-handedconfiguration

  7. 在130区发现的chiral doublet band ： (h11/2g7/2) bands: I (Z=53):118I(N=65) (h11/2h11/2) bands: Cs(Z=55): 126Cs(N=71), 128Cs(N=73), 130Cs(N=75) La(Z=57): 130La(N=73), 132La(N=75), 134La(N=77) Pr(Z=59): 132Pr(N=73) ,134Pr Pm(Z=61) 136Pm(N=75) Er(Z=63): 138Er(N=75)

  8. Chiral Twin Bands in 126-130Cs Z=55, h11/2h11/2

  9. h11/2h11/2band in 122Cs (single) Jingbin Lu et al.J. Phys. G: Nucl. Part. Phys. 25 (1999) 573. C.-B. Moon et al. Nucl. Phys. A 674 (2000) 343.

  10. 中国原子能科学院H-13串列： 19F + 107Ag  122Cs (1p,3n)

  11. Band 1 and 3: h11/2h11/2bnds in 122Cs (doublet).

  12. 651.4 421.2

  13. 问题是：自旋I＝？ Jingbin Lu et al. J. Phys. G: Nucl. Part. Phys. 25 (1999) 573: 基于系统学比较: I=(9+) .

  14. C.-B. Moon et al. Nucl. Phys. A 674 (2000) 343. 角分布测量: I=11. 基于角分布的测量, 132.3 keV为M1跃迁, 则132.3 keV 上面的能级可能为(7+)或(9+), 所以, (7+)也是可能的. (9+) (7+) 我们同意前者的指定, I=(9+)

  15. Chiral doublet bands in 122Cs?

  16. I=9

  17. Question: 122Cs: Z=55 , in top of h11/2, N=67, in middle of h11/2 TRS prediction: 122Cs and 126Cs, ~0º, chiral doublets?

  18. A＝130区核： 134Ce，研究shape coexistence and shape driving

  19. The proton Fermi surface lies in the bottom of the h11/2 subshell, favors a collectively rotating prolate shape (~0); The neutron Fermi surface lies in the top of h11/2 subshell, favors an oblate shape (~-60). Therefore, different configurations of the quasiparticles can drive a nucleus to form different shapes.

  20. E.S.Paul et al. PRL,58, 984(1987)

  21. In CIAE (China Institute of Atomic Energy), H-13 tandem: 16O + 122Sn  134Ce (4n)

  22. S. Lakshmi et al. Phys. Rev. C 69, 014319 (2004) Magnetic rotation bands

  23. B4-(8)

  24. B5—(7)

  25. Life time?—485 ns (4)

  26. h11/2 g7/2 proton configuration

  27. E.S.Paul et al. PRL,58, 984(1987)

  28. [h11/2]-1, -60°, oblete h11/2g7/2, 0° Prolate deformation [h11/2]-1, -120°, prolate =0 -60°, oblete ? =1 2, , g

  29. The 1- 2- bands, The ground state band, The 10+ state above the ground state band (1) with h11/2 quasineutron has an oblate deformation with an asymmetry parameter -60 ; The 10+ isomer (4), with h11/2 quasineutron configuration is a yrast trap of prolate deformation with 120; The other two signature partner bands (5) and (6) with h11/2 and g7/2 proton configuration has a prolate deformation with 0.

  30. 136La: 寻找扁椭形变带. 130Te(11B, 5n)136La , 中国原子能科学研究院北京串列加速器核物理实验室束流能量65/50Mev，强度10nA，背面加铅衬的130Te靶，靶厚. 6mg / cm2 ，铅衬厚度为10mg/cm2 , 14反康高纯锗探测器.

  31. A=130区核中子数比较多的靠近N=82满壳附近的核, 多准粒子带中观测到多条扁椭形变带, 这些扁椭形变带与长椭形变带不同, 特点为: • 强的M1跃迁. • 转动惯量,随转动频率增加而下降.

  32. 136La (Z=57, N=79) E.W.Cybulska et al. Acta Phys. Pol.B32, 929 (1999).

  33. h11/2h11/2 bnds

  34. 原来文献(8+) h11/2h11/2 带的系统学比较

  35. Band (2)

  36. 带(2)带(3)为oblete带(=-60). • 带(2): • 带(3)

  37. 通过对符合数据的分析，共识别了44条跃迁，36个能级，其中新发现或者重新定位的跃迁为13条，新能级11个，自旋态扩展到了25 h • 带（1） • 带（2） • 带（3）

  38. 小结: 我们对A=130区缺中子核的3个核进 行了高自旋态实验研究, 研究其长椭形变、 扁椭形变及形状共存,以及手征二重带特性. 122Cs ---- Chiral doublet bands? 134Ce -----不同形变值的形状共存. 136La ----- h11/2h11/2带与扁椭形变带。

  39. THE END THANKS!

More Related