1、Systematical calculations on superheavy nuclei,Zhongzhou RENDepartment of Physics, Nanjing University, Nanjing, China Center of Theoretical Nuclear Physics, National Laboratory of Heavy-Ion Accelerator, Lanzhou, China,Outline,Introduction Nuclear structure calculations on superheavy nuclei (RMF, SHF
2、, MM) Alpha decay: density-dependent cluster model (DDCM) Spontaneous Fission: new formula on half-lives of SF. Summary,1. introduction: experiments,Z=110 (Ds), 111(Rg), 112 were produced at GSI, Hofmann, Muenzenberg. Z. Phys. A, 1995-1996Z=114-116, 118, at Dubna, by Oganessian et al.Nature, 1999; P
3、RL. 1999;PRC, 2000-2005.Z=110-111, new results, at Berkeley, PRL 2004.Z=113, RIKEN, Morita, J. P. S. J., 2004.270Hs, Duellman, Turler, , Nature 2003, EPJA 04.265Bh, Lanzhou, Gan, Qin, , EPJA 2004.,1. introduction: theory.,J. A. Wheeler, 1950s: Superheavy nuclei Werner and Wheeler, Phys. Rev., 109 (1
4、958) 126.1960s-2000s, macroscopic-microscopic model (MM): Nilsson et al, Z=114 and N=184. 1970s-2000s: Skyrme-Hartree-Fock (SHF) Model; Z=126? N=184? 1990s-2000s: Relativistic Mean-Field model : Z=120 ? N=184? Spherical or deformed for superheavy nuclei ?,2. nuclear structure calculations,2.1. RMF c
5、alculations on superheavy nuclei Z=90-120：binding energies, deformations,Compare RMF with experimental data RMF predictions on experiments Ren et al. , PRC (2002-2005) ; NPA(2003-2005)2. 2 New idea: shape coexistence and superdeformationRen and Toki, 2001, NPA, Ren et al,2.3. Shape coexistence from
6、other models SHF model and MM modelNature 433, 2005. Atom. Data. Nucl. Data Tab. 77 (2001) 311 .,2.1 RMF results and discussion,Nuclei: Z =94120; N=130190. Comparison of theoretical binding energy with exprimental data. Comparison of theoretical alpha decay energy with exprimental data.Comparison of
7、 theoretical quadrupole deformation with exprimental data.,Table 1, RMF results for Pu. (TMA and NLZ2). Experimental Beta2=0.29 for 238-244Pu.,Table 2, RMF results for Cm. (TMA and NLZ2),Experimental deformation Beta2=0.30 for 244-248Cm,Table 5, RMF results for No. (TMA and NLZ2),Experimental deform
8、ation Beta2=0.27 for 254No,Experimental B/A (MeV) is between two sets of RMF results (Z=98-108).,Fig. 3 Binding energy of the Z=112, A=277 alpha-decay chain from the RMF and Moller et al.,Fig. 4 Theoretical and experimental alpha decay energies for GSI Data: Z=110, 111, 112 ( +2, +1, 0 shift).,Tab.
9、10, results for Dubna data 292116. (TMA) (Beta2=0.46, 0.45,0.44 for SHF model.),Tab. 11, results for Dubna data 292116. (NLZ2). (Beta2=0.46, 0.45,0.44 for SHF model).,2 new: shape coexistence,superdeformation,? Ren and Toki, Nucl. Phys. A 689 (2001) 691. Z. Ren, Shape coexistence in even-even superh
10、eavy nuclei, Phys. Rev. C65, 051304 (2002) Z. Ren et al., Phys. Rev. C66, 064306 (2002) Z. Ren et al., Phys. Rev. C67, 064302 (2003) Sharma, ,Munzenberg, PRC, 2005;,Stevenson, Gupta, Greiner, JPG, 2006.S. Goriely, F. Tondeur, J. Pearson, SHF Model Atom Data and Nucl. Data Tables 77 (2001) 311. Super
11、deformation for some superheavy nuclei,Fig. 9 Energy surface of Z=114, A=288.,15. Ren, Z. Shape coexistence in even-even superheavy nuclei. Phys. Rev. C65, 051304 (2002),To be cited: shape coexistence, Ref. 15,Nature, 433 (2005) 475,64. Z. Ren, Phys. Rev. C65, (2002) 051304(R) 65. Z. Ren et al., Phy
12、s. Rev. C66, (2002) 064306,Exp. Def. : 0.28, RMF Def.: 0.26-0.32,cited.,Z. Ren et al, PRC 67 (2003) 064302; NPA 722 (2003) 543. Prediction for 265107 : Qa and Ta,Expt: Gan et al, EPJA 2004, Qa=9.24 , Ta=0.94 s. Good agreement between theory and data.,Theoretical prediction: 265107 Qa and Ta Z. Ren e
13、t 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.,Z. Ren, Prog. Theor. Phys. Supplement, No. 146 (2002) 498 (YKIS01, Japan). RMF prediction for 278113 : Qa and Ta,Morita et al, JPSJ 2004, Qa=11.68, Ta=0.34 ms. Good
14、 agreement between theory and data.,南京大学,Predictions of SHF and RMF compare well with MM results 12,13,Oganessian et al, PRC72 2005,南京大学,SHF 12，49-51 and RMF 13，52-57 compare well with the experimental results,Oganessian et al, PRC72 2005,3. Density-Dependent Cluster Model,DDCM is a new model of alp
15、ha 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-livesZ 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:
16、041301(Rapid Commun.) (2006),3. DDCM for alpha decay: agreement is within a factor of three for half-lives although experimental half-lives vary from 10-6 s to 1019 year,DDCM for superheavy nuclei (Z=106-118),DDCM : 被PRC论文大段引用(共16处),最近文献7,16,18,28研究了超重元素alpha衰变; 如图2为7,18,28的结果.我们的结果和18的结果基于不同的cluste
17、r模型.,文献18得到了超重核alpha衰变寿命好的符合.,文献18提出的结团模型理论很好描述了该区域.,DDCM: 被PRC论文大段引用(共16处),Deformed DDCM: a spherical alpha-particle interacts with a deformed daughter nucleus with an axially symmetric deformation,The double-folding nuclear potential of 236U for two orientations, beta = 0 and beta = 90,In the mult
18、ipole expansion, the density distribution of daughter nucleus is expanded as,The corresponding intrinsic form factor has the form,The double-folding potential can then be evaluated by a sum of different multipole components,The corresponding multipole components are,The polar-angle dependent penetra
19、tion probability of alpha decay is given by,In the DDCM, the alpha-decay width has the following expression,The comparison of experimental alpha-decay half-lives and theoretical ones for even-even nuclei (Z= 52104),The distribution of the number of alpha emitters for different factors of agreement.,
20、4. New formula of half-lives: Ground-State and isomer spontaneous fission.,Long lifetime line of G.S. fission: N=Z+52 Three formulas for G.S. fission.New formula of fission half-lives of 33 isomers: log10(T1/2) = -6 + c1(Z-92) + c2(N-Z-52)(N-146) + c3 C Xu, Z Ren, PRC 71: 014309 (2005) Z Ren, C Xu,
21、NPA 759: 64 (2005),.,Very good agreement for SF half-lives of isomers,Summary,Nuclear structure calculation : Agreement with data and new predictions Shape coexistence: isomers of superheavy nuclei; maybe superdeformation More and more people agree since 2005.Density-dependent cluster model of alpha
22、 decay (spherical and deformed) New formulas for spontaneous fission: Ground state and isomeric state,Thanks,国外同行对我们工作的引用和肯定,国内外同行对我们工作的引用和肯定,Geng, Toki, Zhao JPG 32 (2006) 573: 超重核有形状共存, 大形变, 与我们结果一致.,编写电子和晕核散射新程序： 相对论Eikonal近似,1. 理论结果与现有实验数据非常符合 2. 预言电子-丰质子核散射,能清楚探测质子晕 结构, 这是电子-质子晕核散射的第一个理论结果 3. 为将来的电子-丰质子核对撞实验预研参考文献 Z Wang, Z Ren, PRC 70: 034303 (2004) Z Wang, Z Ren, PRC 71: 054323 (2005) ,编写电子和晕核散射新程序： 相对论Eikonal近似,
