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超重核 ( 新元素 ) 研究进展 任中洲 南京大学 物理学院. 寻找重元素的历史回顾 实验的新进展 理论研究状况 Z=118 新元素的合成 (Dubna). 周期表 (1869): 门捷列夫未获 Nobel Prize. 周期表 (2000). WebElements: the periodic table. 化学元素周期表 2008. 117. Cn 112. 117. 超重元素研究现状 (Z=112, Cn).

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超重核(新元素)研究进展 任中洲南京大学 物理学院

  • 寻找重元素的历史回顾

  • 实验的新进展

  • 理论研究状况

  • Z=118新元素的合成(Dubna)


1869 nobel prize
周期表 (1869): 门捷列夫未获 Nobel Prize


周期表(2000)


Webelements the periodic table
WebElements: the periodic table

化学元素周期表2008


117

Cn

112

117

超重元素研究现状 (Z=112, Cn)

R. Eichler et al, NATURE, Vol.447(2007)72, Chemical characterization of element 112

Oganessian et al., Phys. Rev. Lett. 104, 142502 (2010)

Synthesis of a New Element with Atomic Number Z=117


近年来研究超重原子核(新元素) 的性质是国际核物理的热点之一.

核素图


1寻找重元素的历史

  • 早期物理学家寻找新化学元素

  • 物理学+化学:

  • 光谱线: Fraunhofer, Kirchhoff +Bunsen (Germany): Cs, Rb (37,55); Crookes, Tl(81).

  • 物理学+天文学:

  • 日蚀时,观察新光谱线 ,太阳元素:氦

    法国物理学家,英国天文学家(1868).

    为什么物理学家介入:物理方法威力大。


1903 1904 nobel prize and new elements
1903-1904: Nobel Prize and new elements

  • 1. Rayleigh(physicist: N) +Ramsy (chemist):

    Ar; He (Crookes: confirm), Ne ,Kr

  • 1904 Nobel prize ( Physics+Chemistry)

  • 2. M.Curie and P. Curie: Radioactivity;

  • Stronger : new elements, Ra, Po (1898) ?

  • 1903 Nobel prize (Physics) 1/2+(1/4+1/4)

  • 1911 Nobel prize (Chemistry)



Brief introduction g s important decay modes of nuclei
Brief Introduction : (g.s.)Important decay modes of nuclei

Proton emission (Z >51)

Alpha decay (Z>=52)

Cluster radioactivity (Z >=87)

Spontaneous fission (Z >= 90)


References on arguments
References on arguments

  • 1. A history of physics, Dover Publications, F. Cajori , 1962, USA.

  • 2. Une Femme Honorable, Marie Curie;

  • De Francoise Giroud;

  • Librairie Artheme Fatard, 1981.

  • 3. A short history of nearly everything,

  • Bill Bryson, Jed Mattes Inc. , 2003



学术争论双刃剑

  • M. Curie won the Nobel Prize of Chemistry in 1911. newspaper ?

  • Boltzman, argument on the existence of atoms…

  • Ehrenfeste ? Quantum mechanics.…


1 寻找新元素的历史

  • 周期表中30多个元素由核方法合成

  • 1930—1949 找到“失踪”元素

  • 重元素 (U 以后:Z=93,94?)合成

  • 核合成的元素被化学家证实

    为什么核合成? 稀有 或 放射性。



重元素合成的意义 (1)

  • 扩展元素周期表

  • 到底有多少个化学元素 ?

  • 新元素的应用?超重岛存在?

  • 超重岛存在机制? 新现象?


元素的合成和命名

Z=101, Mendelevium (Berkeley).

Z=102, Nobelium (Berkeley +Nobel)

Z=103, Lawrencium. (Berkeley)

Z=104, Rutherfordium. (Berkeley;Dubna ?)

Z=105, Db, Dubnium (Dubna;Berkeley ?)

Z=106, Seaborgium. (Dubna;Berkeley !)

Z=107, Bohrium (Dubna)

Z=108, Hassium (GSI; Dubna ?!)

Z=109, Meitnerium. (GSI)

Z=110, Ds, Darmstadium Z=111, Rg, Roentgenium Z=112, Cn, Copernicium (GSI)




2 summary of new results
2. Summary of New Results

  • The elements Z=110,111,112 were produced at

    GSI, Hofmann, Muenzenberg…. Z. Phys. A, 1995, 1996.

  • Z=114 was synthesized at Dubna by Oganessian et al.

    Nature, 1999; Phys. Rev. Lett. 1999;Phys. Rev. C, 2000.

  • Z=116 , Z=115, Z=118 were produced at Dubna in 2000s.

    Oganessian et al, Phys. Rev. C, 2001-2006. Z=117, 2010

  • Z=113, RIKEN; PSI: 270 108; GSI: 270110 ; Lanzhou: 265107…. 继续争论??? 新元素???


265Bh

0.94 s

9.24 a

259Db

0. 5 s

9.47 a

超重新核素259Db (Z=105),265Bh (Z=107)

中科院近代物理研究所


265bh z 107
国内超重新核素实验265Bh (Z=107)

265Bh的实验结果与理论预言一致


最新超重核评述文章:Oganessian JPG 2007


3 theory
3. theory.

  • J. A. Wheeler et al, 1950s: Superheavy nuclei

  • P.R., 1958.

  • Bethe and his collaborator, PRL, 1967.

  • 1960s-1980s, macroscopic-microscopic model (MM): Nilsson et al, Z=114 and N=184 ?

  • Moeller, Nix, Kratz, At. Dat. Nu. Dat. 1997.

  • Myers and Swiatecki, PRC, 1998.



Siemens and bethe nuclei with z 104 are prolate
Siemens and Bethe: nuclei with Z>104 are prolate


3 theory shf and rmf 1990
3. Theory ( SHF and RMF 1990--)

  • Zhongzhou REN et al, JPG, 1996; CPL, 1997.

  • Lalazissis, Ring et al, NPA, 1996.

  • Cwiok, Nazarewicz, Heenen, PRL, 1999.

  • Ren and Toki, Nucl. Phys. A689 (2001) 691: Z=110-112,114. Ren, PRC, 2002,May,(R);PRC, Dec.,2002

  • Ren et al, PRC 2003, PRC2004, PRC2005...


Relativistic mean field model
Relativistic mean-field model

  • Protons and neutrons interact by exchanges of mesons (strong interactions)

  • There is the electromagnetic interactions among protons by exchange of photons

  • Atomic nucleus is a many-body system

  • Solve the coupled Dirac equations

  • and the Klein-Gordon equations


3 numerical results and discussion
3. Numerical results and discussion

  • Z: 94—116; N:150—184. Test the model for even-even nuclei:

  • Comparison of RMF model and Moeller

    result for the alpha chain of 277112.

    * Theoretical decay energy for Z=110-112.

    Theoretical decay energy for Z=114, 116.

    Nuclear structure : Shape coexistence in superheavy nuclei


Fig 3 theoretical and experimental alpha decay energies for gsi data z 110 111 112 2 1 0 shift
Fig. 3 Theoretical and experimental alpha decay energies for GSI Data: Z=110, 111, 112 ( +2, +1, 0 shift).


Table 1 rmf results for cf tma and nlz2
Table 1, RMF results for Cf. ( GSI Data: Z=110, 111, 112 ( +2, +1, 0 shift).TMA and NLZ2)

Experimental deformation Beta2=0.30 for 250,252Cf


Table 2 rmf results for no tma and nlz2
Table 2, RMF results for No. ( GSI Data: Z=110, 111, 112 ( +2, +1, 0 shift).TMA and NLZ2)

Experimental deformation Beta2=0.27 for 254No


Fig 1 energy surface of z 108 a 264
Fig. 1 Energy surface of Z=108, A=264 GSI Data: Z=110, 111, 112 ( +2, +1, 0 shift).



Fig 2 binding energy of the z 112 a 277 chain from the rmf and moller et al
Fig. 2 Binding energy of the Z=112, A=277 chain (Z=98-108). from the RMF and Moller et al.


Tab 4 results for gsi data 269 110 tma
Tab. 4, results for GSI data (Z=98-108).269110. (TMA)



创新点及意义 Z=114, A=289 and Z=118, A=293(1)

  • 提出超重核形状共存----可能是超重核存在新机制:

  • 改进和发展了数值计算方法和程序

  • 完成大规模数值计算

  • 提出超重核形状共存, 形变重要, 有低能同质异能态

  • 发表了一系列论文(PRC 3篇; NPA 2篇等)

  • 论文被国外同行引用和肯定:

  • 论文被国际上著名实验小组引用(Dubna-Livemore-PSI)

  • 论文被综述文章引用(Nature, PRC, JPG)


Oganessian et al prc72 2005
Oganessian et al, PRC72 2005 Z=114, A=289 and Z=118, A=293

Predictions of SHF and RMF compare well with MM results [12,13]

南京大学


Oganessian et al prc72 20051
Oganessian et al, PRC72 2005 Z=114, A=289 and Z=118, A=293

SHF [12,49-51] and RMF [13,52-57] compare well with the experimental results

南京大学


15 ren z shape coexistence in even even superheavy nuclei phys rev c65 051304 2002
15. Ren, Z. Shape coexistence in even-even superheavy nuclei. Phys. Rev. C65, 051304 (2002)

Cited: shape coexistence, Ref. [15]

Nature, 433 (2005) 705


64 z ren phys rev c65 2002 051304 r 65 z ren et al phys rev c66 2002 064306
64. Z. Ren, Phys. Rev. C65, (2002) 051304(R) nuclei. Phys. Rev. C65, 051304 (2002) 65. Z. Ren et al., Phys. Rev. C66, (2002) 064306

Exp. Def. : 0.28, RMF Def.: 0.26-0.32,cited.


…Z. Qin, nuclei. Phys. Rev. C65, 051304 (2002)形变双幻核270Hs:理论预言与实验一致


Sharma stevenson gupta greiner agree with us shape coexistence and superdeformation
Sharma,… Stevenson, Gupta, Greiner agree with us: nuclei. Phys. Rev. C65, 051304 (2002)shape coexistence and superdeformation


Geng toki zhao similar results with us
Geng, Toki, Zhao: similar results with us. nuclei. Phys. Rev. C65, 051304 (2002)


Geng toki zhao jpg 32 2006 573 shape coexistence and superdeformation
Geng, Toki, Zhao JPG 32 (2006) 573: nuclei. Phys. Rev. C65, 051304 (2002)shape coexistence and superdeformation.


Other rmf calculations agree with ours superdeformation in superheavy nuclei
Other RMF calculations agree with ours: nuclei. Phys. Rev. C65, 051304 (2002)superdeformation in superheavy nuclei


265 107 q a and t a z ren et al prc 67 2003 064302 jnrs 3 2002 195
配合国内实验 nuclei. Phys. Rev. C65, 051304 (2002), 理论预言: 265107 Qa and Ta Z. Ren et al, PRC 67 (2003) 064302; JNRS 3 (2002) 195.

Expt: Gan et al, EPJA 2004, Qa=9.38 , Ta=0.94 s.

Good agreement between theory and data.


265bh z 1071
国内超重新核素实验 nuclei. Phys. Rev. C65, 051304 (2002)265Bh (Z=107)

265Bh的实验结果与理论预言一致


3 density dependent cluster model
3. Density-Dependent Cluster Model nuclei. Phys. Rev. C65, 051304 (2002)

  • DDCM is a new model of alpha and cluster decay:

  • 1) effectve potential based on the Reid potential.

  • 2) low density behavior included.

  • 3) exchange included

  • 4) agreement within a factor of three for half-lives

  • Z Ren, C Xu, Z Wang, PRC 70: 034304 (2004)

  • C Xu, Z Ren, NPA 753: 174 (2005)

  • C Xu, Z Ren, NPA 760: 303 (2005)

  • C. Xu, Z. Ren, PRC 73: 041301(R) (2006)…


Ddcm for superheavy nuclei z 106 118
DDCM for superheavy nuclei (Z=106-118) nuclei. Phys. Rev. C65, 051304 (2002)


Density dependent cluster model
Density-Dependent Cluster Model nuclei. Phys. Rev. C65, 051304 (2002)

  • 建立了球形和形变核双折叠势程序

  • 推导了球形,形变核alpha衰变寿命公式

  • 对已知alpha衰变寿命进行了大规模计算

  • 对结团放射性进行了系统研究


Density dependent cluster model of alpha decay
Density-dependent cluster model of alpha decay nuclei. Phys. Rev. C65, 051304 (2002)

The Reid

nucleon-nucleon potential

Bertsch et al.

Nuclear Matter: G-Matrix

M3Y

Satchler et al.

Hofstadter et al.

1/30

Electron Scattering

DDCM

Alpha Scattering

RM3Y

Brink et al.

Tonozuka et al.

Nuclear Matter

Alpha Clustering (1/3)

1987PRL

Alpha Clustering


Deformed DDCM: a spherical alpha-particle interacts with a deformed daughter nucleus with an axially symmetric deformation


The distribution of the number of alpha deformed daughter nucleus with an axially symmetric deformationemitters for different factors of agreement (Even-Even).


The comparison of experimental alpha-decay half-lives and theoretical ones for even-even nuclei (Z= 52−104)


国外同行引用举例 theoretical ones for even-even nuclei (Z= 52−104)(三)

论文被引用:理论核形变与新实验结果一致

[46] C. Xu, Z. Ren, Phys. Rev. C 75 (2007) 044301


Prc2010
国外同行引用举例 theoretical ones for even-even nuclei (Z= 52−104)(四):PRC2010

Ismail follows Refs. [8-9].

多处引用我们工作[8-9].


国外引用 theoretical ones for even-even nuclei (Z= 52−104)(四): follow us


国外引用 theoretical ones for even-even nuclei (Z= 52−104)(四):follow us,全文13处引用

They use more recent values that were

proposed in Ref. [60].


北大和理论所的工作举例 theoretical ones for even-even nuclei (Z= 52−104)

该文引用了我们的工作: 见下页


国内同行引用举例(一) theoretical ones for even-even nuclei (Z= 52−104)

从折叠模型获得的微观势被成功地应用到alpha衰变和alpha散射的计算中 [9-12]


国内同行引用举例(一) theoretical ones for even-even nuclei (Z= 52−104)

文献[39,40]指出形变可以影响alpha衰变的寿命


原子能院和北航工作(二) theoretical ones for even-even nuclei (Z= 52−104): 五篇被引

Zhang et al.,

PRC80 2009

This is in agreement with Ref. [40].

这与文献 [40] 一致


Heavy and superheavy nuclei npa 825 145 158 2009
Heavy and superheavy nuclei theoretical ones for even-even nuclei (Z= 52−104)NPA 825 145-158 (2009)


Solve s eq for quasi bound state
Solve S-eq. for quasi-bound state theoretical ones for even-even nuclei (Z= 52−104)

Woods-Saxon shape nuclear potentials

V0 is determined by the characteristic of the alpha-cluster quasibound state.


Generalized ddcm prc 80 014314 2009
Generalized DDCM : theoretical ones for even-even nuclei (Z= 52−104)系列工作, 量子PRC 80 014314 (2009)……


Alpha 2009 2010
我们小组 theoretical ones for even-even nuclei (Z= 52−104)alpha衰变寿命工作(2009-2010)

  • 2009-2010建立推广的密度依赖结团模型GDDCM,解准束缚态薛定谔方程,纯量子模型:

    Ni and Ren NPA 825, 145 (2009); 828, 348 (2009); PRC 80, 014314 (2009); 80, 051303(R) (2009);81, 024315 (2010).

  • 2010建立计算形变核alpha衰变寿命和分支比的新模型—多道结团模型(MCCM),第一次完成四道耦合自洽计算:

    Ni and Ren PRC 81, 064318 (2010)....


准束缚态问题来源 theoretical ones for even-even nuclei (Z= 52−104)

  • 量子力学源于原子物理:束缚态,散射态(教科书)

  • 1928,Gomov用量子力学定性解释原子核α衰变

  • 不稳定原子核的特点:有限寿命—准束缚态(Q-BS)

  • 已有理论模型:半经典或准经典近似(WKB, Bohr-Sommerfeld quantization)

  • α衰变是一个纯量子效应,应解准束缚态薛定谔方程

  • GDDCM is a new version of DDCM:

  • 1) pure quantum version of decay

  • 2) wave functions are obtained by S-eq. for Q-BS.


Woods-Saxon theoretical ones for even-even nuclei (Z= 52−104)势球形核准束缚态波函数

Woods-Saxon shape nuclear potentials

V0 is determined by the characteristic of the alpha-cluster quasibound state.


The number of internal nodes is determined theoretical ones for even-even nuclei (Z= 52−104)

by the Wildermuth condition

Behaving like the irregular Coulomb

wave function


新版本密度依赖结团模型: theoretical ones for even-even nuclei (Z= 52−104)PRC 80 (2009) 051303(R)

微观计算形变核alpha衰变寿命


形变核 theoretical ones for even-even nuclei (Z= 52−104)alpha衰变新模型:多道结团模型(MCCM)


Mccm s eq

0 theoretical ones for even-even nuclei (Z= 52−104)+

248Cf

Exp.

Cal.

---

0.0046%

6+

0.79%

0.40%

4+

19.98%

19.60%

2+

80.00%

79.22%

0+

T1/2(s) 2.88*1072.43*107

多道结团模型(MCCM): 准束缚态耦合S-eq.


0 theoretical ones for even-even nuclei (Z= 52−104)+

0+

248Cf

250Cf

Exp.

Exp.

Cal.

Cal.

---

0.010%

0.0046%

0.0039%

6+

6+

0.79%

0.40%

0.70%

0.30%

4+

4+

19.98%

19.60%

18.56%

15.00%

2+

2+

80.00%

79.22%

84.70%

80.74%

0+

0+

T1/2(s) 2.88*1072.43*107

T1/2(s) 4.13*1083.29*108

Calculated results for two isotopes of Cf


0 theoretical ones for even-even nuclei (Z= 52−104)+

0+

252Fm

254Fm

Exp.

Cal.

Exp.

Cal.

0.0066%

0.023%

0.013%

0.014%

6+

6+

1.08%

0.82%

1.15%

0.97%

4+

4+

17.81%

14.20%

19.62%

15.00%

2+

2+

81.09%

85.00%

84.00%

79.22%

0+

0+

T1/2(s) 1.17*1041.01*104

T1/2(s) 9.14*1044.82*104

Calculated results for two isotopes of Fm


Synthesis of new element z 118

Synthesis of new element Z=118 theoretical ones for even-even nuclei (Z= 52−104)

1. 2002, Dubna: D7-2002-287

2. PRC69, 2004 (May).

3. PRC70, 2004 (Dec.).

4. Phys. Scrt. 2006 (June)

5. PRC 74, 2006 (October).


Oganessian prc69 2004 z 118
Oganessian PRC69 (2004): Z=118 theoretical ones for even-even nuclei (Z= 52−104)


Oganessian prc69 2004 z 1181
Oganessian PRC69 (2004): Z=118 theoretical ones for even-even nuclei (Z= 52−104)


Oganessian prc74 2006 z 118
Oganessian PRC74 (2006): Z=118 theoretical ones for even-even nuclei (Z= 52−104)


Aps physics news update october
APS: Physics News Update October theoretical ones for even-even nuclei (Z= 52−104)


Xu and ren prc 69 2004 feb
Xu and Ren, PRC 69 (2004) (Feb.) theoretical ones for even-even nuclei (Z= 52−104)


Various shapes of superheavy nuclei
Various shapes of superheavy nuclei theoretical ones for even-even nuclei (Z= 52−104)

  • Old picture: Spherical. Z=114 and N=184.

  • Prof. Greiner: Fullerene (Buckyball, 60C). (sixty alpha particles for Z=120 )

  • Our idea: American football . (Isomers)

    ( shape coexistence or superdeformation).

  • Which shape do you prefer ?


Superheavy nuclei american football round ball soccer 60 c
Superheavy nuclei: American football; round ball; Soccer ( theoretical ones for even-even nuclei (Z= 52−104)60C)


Z 122 2008 04
新元素 theoretical ones for even-even nuclei (Z= 52−104)Z=122 ? (2008. 04)


To produce z 117 element in china
To produce Z=117 element in China? theoretical ones for even-even nuclei (Z= 52−104)

  • We estimate the alpha-decay energies and half-lives of Z=117 elements.

  • We will estimate the spontaneous

    fission half-lives of Z=117 element.

    The goal of 973 of Nuclear Physics: 2007-2012


Synthesis of the 117 theoretical ones for even-even nuclei (Z= 52−104)th element, PRL


遗憾 theoretical ones for even-even nuclei (Z= 52−104); 我们2003提出, 希望国内完成

  • 俄国人和美国人捷足先登

  • 我们判断正确 Z=117

  • 国内实验落后


3 summary 1
3. Summary (1) theoretical ones for even-even nuclei (Z= 52−104)

  • The properties of even-even nuclei with Z=94—116 are investigated in the RMF model.

  • The constraint RMF calculation shows clearly the coexistence of shape in superheavy nuclei. This is useful for a deeper binding and may be a new mechanism of appearance of superheavy islands.


3 summary 2
3. Summary (2) theoretical ones for even-even nuclei (Z= 52−104)

  • We propose new models of alpha decay:

  • Density-dependent cluster model (DDCM)

  • Multi-channel cluster model (MCCM).

  • Agree well with known data.

  • Good prediction for unknown half-lives.


  • 谢 谢! theoretical ones for even-even nuclei (Z= 52−104)

    THANKS!


元素的命名 theoretical ones for even-even nuclei (Z= 52−104)

Z=101, Md, Mendelevium. (Berkeley).

Z=102, No. Nobelium (Berkeley +Nobel)

Z=103, Lr, Lawrencium. (Berkeley)

Z=104, Rutherfordium. (Berkeley;Dubna) ?

Z=105, Db, Dubnium (Dubna;Berkeley) ?

Z=106, Seaborgium. (Dubna;Berkeley) ?

Z=107, Bohrium (Dubna)

Z=108, Hassium (GSI; Dubna) ???

Z=109, Meitnerium. (GSI)

Z=110, Darmstadium…. (GSI)


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