Synthesis of superheavy elements with Z =112-120 in hot fusion reactions

1. Synthesis of superheavy elements with Z =112-120 in hot fusion reactions Wang Nan College of Physics, SZU Collaborators: S G Zhou, J Q Li, E G Zhao,W. Scheid Huzhou Apr. 13th 2012

2. Contents • Introduction • Formalism • Results and discussions • Summary

3. Periodic Table for Chemistry Elements

6. • Experimental achievements: Super-heavy elements up to Z=118 have been synthesized experimentally. Z=107-113: cold fusion, 208Pb/209Bi based reactions by evaporating 1 or 2 neutrons (Rev.Mod.Phys.72(2000)733, Rep.Prog.Phys.61(1998)639) Z=112-118: 48Ca induced fusion reactions, 48Ca bombarding actinide targets by evaporating 3-5 neutrons (J.Phys.G34(2007)R165, NPA787(2007)343c) GSI: 107-112 Dubna: 112-118 Riken: 113 IMP: 259Db, 265Bh Question: How many nucleons can stay together in nucleus?

7. Theoretical models for SHN production Macroscopic dynamical model S. Bjornholm and W.J. Swiatecki, NPA 391 (1982) 471 Fluctuation-dissipation model Aritomo et al. PRC 59 (1999) 796, Shen Int. J.Mod. E 17(2008)66 , Liu & Bao Phys.Rev.C 80(2009)034601 Nucleon collectivization model (Zagrebaev et al.PRC65(2001)014607) Dinuclear system model Adamian et al. NPA 618(1997) 176 Li, Wang et al. EPL 64 (2003) 750, Eur. Phys. J. A 24, 223 (2005) ，J. Phys. G32 (2006) 1143. Feng et al., NPA 771 (2006) 50 Huang et al, PRC 84 (2011) 064619 Wang, Zhao, Scheid , Zhou 85,041601(R)(2012) Other model Wang et al84, 061601(R) (2011)

8. T capture P CF fusion • CN • EN evaporation Schematic picture of the formation of SHN Dinuclear system (used to describe deep inelastic collisions of heavy systems): V.V. Volkov, Phys. Rep. 44(1978)93 Evaporation residue cross section:

9. Capture of two colliding nuclei Transmission probability calculated from barrier distribution: The value of 1 is 2-4 MeV less than the one of 2

10. Formation of compound nucleus - Master equation Hamiltonian

11. Dynamical Potential Energy Surface(Dyn-Pes) Driving potential(Potential Energy Surface) Dynamical deformation satisfy

12. Dynamical Potential Energy Surface(Dyn-Pes)

13. Survival probability of excited compound nucleus The thermal compound nucleus will decay by evaporating -ray,light particles and fission. The survival probabilities can be written as

14. Results and discussions Capture and evaporation residue cross sections for Ca48+U238 Exp. Yu.Ts. Oganessian, et al., PRC 70 (2004) 064609

15. Evaporation residue cross sections for Ca48+U238, Np237 Exp. Yu.Ts. Oganessian et al., PRC 70 (2004) 064609

16. Evaporation residue cross sections for Ca48+Pu242, Pu244 Exp. Yu.Ts. Oganessian et al., PRC 70 (2004) 064609

17. Evaporation residue cross sections for Ca48+Am243, Cm248 Exp. Yu.Ts. Oganessian et al., PRC 74.044602

18. Evaporation residue cross sections for Ca48+ Bk249, Cf249 Exp. Yu.Ts. Oganessian et al., PRC 74.044602

19. Evaporation residue cross sections for Ca48+U-Cf Exp. Yu.Ts. Oganessian et al., PRC 74.044602

20. About element Z=120

24. Evp. cross sections for nuclei Z=120 Dash dot: Ti+Cf249 Solid: Cr+Cm248 Dashed: Fe+Pu244 Fusion probability for nuclei Z=120

25. Lifetime for some Cf isotopes

26. Evp. Cross sections for some Ti+ Cf isotope reactions

28. About element Z=119

30. Evp. Cross sections for Cr+ Am and Fe+Np reactions leading to nuclei with Z=119

31. Lifetime for some Bk isotopes

32. Evp. Cross sections for some Ti+ Bk isotope reactions

33. Summary • Some evaporation residue cross sections for 112-118 are studied with dyn-pes DNS model . The calculated results are in good agreements with experimental • Several combinations for Z=119, 120 are calculated . Some reactions are suggested.

34. Thanks 谢谢