Synthesis of superheavy nuclei in heavy-ion reactions with transuranium targets

1. Synthesis of superheavy nuclei in heavy-ion reactions with transuranium targets Wang Nan College of Physics, SZU Collaborators: S G Zhou, E G Zhao, J Q Li,W. Scheid Beijing Jun. 15th 2012

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

3. Periodic Table for Chemistry Elements

5. 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 heavy element can we produce?

6. Theoretical models for SHN production Macroscopic dynamical model S. Bjornholm and W.J. Swiatecki, NPA 391 (1982) 471 Fusion by diffusion model Aritomo et al. PRC 59 (1999) 796, Shen Int. J.Mod. E 17(2008)66 , Liu & Bao Phys.Rev.C 80(2009)034601 , K. Siwek-Wilczynska, T. Cap, and J. Wilczynski, Int. J. Mod. Phys. E 19, 500 (2010) 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(2012) 041601(R) Other model Wang et al84, 061601(R) (2011)

7. 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:

8. 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

9. Formation of compound nucleus - Master equation Hamiltonian

10. Driving potential Driving potential(Potential Energy Surface) Intrinsic energy Dynamical deformation satisfy

11. Driving potential

12. 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

13. Results and discussions Capture cross sections for 48Ca + 238U, 237Np, 242Pu, 244Pu, 243Am, 248Cm, 249Bk and 249Cf

14. Potential energy surface and Pcn for 48Ca+238U

15. Fusion probabilities for some hot fusion reactions

16. Survival probabilities for some compound nuclei produced in hot fusion reactions

17. Evaporation residue cross sections for 48Ca+238U, 237Np Exp. Yu.Ts. Oganessian, et al., PRC 70 (2004) 064609

18. Evaporation residue cross sections for 48Ca + 242, 244 Pu Exp. Yu.Ts. Oganessian et al., PRC 70 (2004) 064609 P. A. Ellison, et al, Phys. Rev. Lett. 105, 182701 (2010)

19. Evaporation residue cross sections for 48Ca+243Am, 248Cm Exp. Yu.Ts. Oganessian et al., PRC 70 (2004) 064609 S. Hofmann, S. Heinz, R. Mann, et al., Euro. Phys. J. A 48, (2012) 1

20. Evaporation residue cross sections for 48Ca +249Bk, 249Cf Exp. Yu.Ts. Oganessian et al., PRC 74.044602(2006) PRC 76, 011601(R) (2007)

21. Evaporation residue cross sections for the SHN 112-120

22. About SHN Z=120

26. Evaporation residue cross sections for nuclei Z=120

27. Lifetime for some Cf isotopes

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

29. About SHN 119

31. Evp. Cross sections for 50Ti+ 249Bk, 54Cr+ 243Am and 58Fe+237Np reactions leading to nuclei with Z=119

32. Lifetime for some Bk isotopes

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

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

36. Thanks 谢谢