Advances in Heavy Ion Nuclear Physics at JINR

1. Heavy ion nuclear physics in JINR /present and future/ Yuri Oganessian FLNR JINR 28-th of Nucl. Phys. PAC meeting June 19-20, 2008, JINR, Dubna

2. ? H. Jensen, E.P. Wigner and M. Goeppert-Mayer Nobel prize 1963 protons 82 126 50 50 Nuclear shells Nuclear shells 82 28 20 Exotic area 50 28 8 2 neutrons 20 Lightest nuclear 2 8 Heaviest nuclei Yu. Oganessian. Heavy Ion Physics in JINR. 28-th PAC meeting, June 19-20, JINR, Dubna

3. huge rotation high temperature spin up to 66h T~ few MeV (>1010K) After it has been shown that a nucleus can endure a giant deformation axes up to 3:1 and finally survive….

4. two-proton decay Fe Radioactive ion beams 0.8s 0.1s beams Shells in the light nuclei Shells in the light nuclei

5. Neutron-rich unstable nuclei Neutron-rich unstable nuclei Yu. Oganessian. Heavy Ion Physics in JINR. 28-th PAC meeting, June 19-20, JINR, Dubna

6. Strangely enough, but all the combinations: 3H, 6He, 8He (beams) + 1H, 2H, 3H (targets) have been studied. Now the structure of the lightest nuclei looks as follows:

7. strong shell effect in the “doubly-magic” nucleus evidence of shell structure discovery “di-neutron” in halo-nucleus 6He FLNR 2001 no shell effect was observed unbound S2n = -1.07 MeV A.N. Ostrowski et al., HMI 1994 S2n = -1.2 MeV A.A. Korsheninnikov et al., RIKEN 1994 S2n = -3.0 MeV G.M. Ter-Akopian et al., FLNR 2008

8. 5·109/s on the target ACCULINA++ High intensity of now6He: 5·107/s on the target Dubna Radioactive Ion Beams 400-cm cyclotron radioactive ion beams low energy beam line ISOL now 8He Electron accelerator 400-cm cyclotron DIRECT stable ion beams:7Li 11B, 15N, 18O,…48Ca DIRECT

9. For the nuclei with large neutron (and proton) • excess the shell model does not work. • New theoretical concepts require more detailed data on • the structure of these nuclei. • Development of the DRIBs complex connected with: • - an increase in the intensity of stable beams at • the U-400M by 10-20 times • - energy variation of the radioactive beams • creation and putting into operation the ACCOULINA-2 • will allow us to carry out these investigations much more • efficiently.

10. Chart of nuclides Chart of nuclides Spontaneous fission TSF = 2·10-7y TSF < 10-14s TSF = 1016y Macroscopic theory (Liquid Drop Model) about 50 years ago… 102No / Tα≈ 2 s Th Bi 92U / Tα= 4.5·109 y 82Pb / stable

11. Clusters in the decay modes of the 234U nucleus 4He 208Pb 132Sn Yu. Oganessian. Heavy Ion Physics in JINR. 28-th PAC meeting, June 19-20, JINR, Dubna

12. -5 0 5 10 15 LogT1/2 s New lands New lands New lands New lands 1µs 1s 1h 1My 1y Island of Stability Island of Stability 120 r e b shoal shoal m u 110 n n o t peninsula peninsula o r P 100 continent continent 90 80 70 150 170 100 110 130 140 190 120 160 180 Neutron number Sea of Instability Yu. Oganessian. Heavy Ion Physics in JINR. 28-th PAC meeting, June 19-20, JINR, Dubna

13. Cold fusion Hot fusion Neutron capture Reactions of synthesis Yu. Oganessian. Heavy Ion Physics in JINR. 28-th PAC meeting, June 19-20, JINR, Dubna

14. Reactions of Synthesis Reactions of Synthesis Cold fusion Cold fusion Act.+48Ca Act.+48Ca Neutron capture Neutron capture Hot fusion Hot fusion SHE protons → actinides Pb neutrons → Yu. Oganessian. Heavy Ion Physics in JINR. 28-th PAC meeting, June 19-20, JINR, Dubna

15. Cold & hot fusion cross sections Cold & hot fusion cross sections fusion survival SHE

16. Search for Element 116 in248Cm +48Ca reaction Search for Element 116 in248Cm +48Ca reaction chemical separation “in flight” separation 292116 293116 FLNR, Dubna, Russia* LLNL, Livermore, CA 2002 GSI, Darmstadt, Germany* LBL, UC Berkeley, CA Univ. of Mainz, Germany LANL, Los Alamos, NM EIR, Würenlingen, Switzerland 1985 upper limit

17. ACCELERATORS ISOTOPE ENRICHMENT TARGET TECHNOLOGY NEW RECOIL SEPARATOR REACTOR REGIME Efforts focused on the synthesis of SHE Efforts focused on the synthesis of SHE New ECR-ion source (GANIL, JINR) Enrichment up to 68-70% (Lesnoy) 48Ca technology of the target preparation – 0.3mg/cm2 Separation and detection of superheavy nuclei New separator & detectors (Dubna, Livermore) isotope enrichment 98-99% S-2 separator (Sarov) New target matter isotope production high flux reactors (Oak Ridge, Dimitrovgrad)

18. Decay chains Decay chains 237Np 243Am 242Pu, 245Cm 244Pu, 248Cm 85 decay chains was registered 249Cf 34 nuclides FLNR 2000-2006 48Ca +

19. Spontaneous fission half lives Spontaneous fission half lives Actinides Superheavy nuclei Trans-actinides

20. Alpha-decay energies Alpha-decay energies Theory: I. Muntian, Z. Patyk, A. Sobiczewski, Acta Phys. Pol. B 34 (2003) 2073. Experiment: black – light ion induced reactions blue – cold fusion red – Act. + 48Ca reaction Yu. Oganessian. Heavy Ion Physics in JINR. 28-th PAC meeting, June 19-20, JINR, Dubna

21. Theory and Experiment Theory and Experiment spherical nuclei deformed nuclei cold fusion 48Ca-induced reactions

22. The main prediction of the modern microscopic theory of the atomic nuclei about beginning new nuclear shells with an “Islands of Stability” in the region of hypothetical very heavy (superheavy) elements have been confirmed not only qualitatively but in some sense quantitatively. Then there is a direct way to move further, to the region of heavier nuclei, to the study of fundamental properties of atomic nuclei which have been previously inaccessible.

23. Within 6 years: In 26 experiments aimed at the synthesis of superheavy elements a 48Ca total beam dose of 2.2∙1020 was collected. At an average beam intensity of 0.5 pµA (so far it is record) the irradiation of targets lasted non-stop for 3 years! Now at an average beam current of 5 pµA (which is feasible at accelerators and methodologically accepted) these experiments will only take no longer than 1/2 years! Limiting the number of the experiments (the line of research is clear), increasing the beam intensity and putting into operation new effective set-ups one can increase the sensitivity by 50-100 times!

24. It definitely brings not only a qualitative leap in the setting of experiments previously inaccessible, but opens up absolutely new pages in the studies of nuclear and atomic structures.

25. Nuclear density of the SHE Nuclear density of the SHE Z=120, A=298-300 60 α-particles + 60 neutrons α n α n α α n 292120 294118 was produced in 249Cf+48Ca reaction Yu. Oganessian. Heavy Ion Physics in JINR. 28-th PAC meeting, June 19-20, JINR, Dubna

26. available for chemical studies Act.+48Ca α-decay Cold fusion

27. Atomic properties Atomic properties Yu. Oganessian. Heavy Ion Physics in JINR. 28-th PAC meeting, June 19-20, JINR, Dubna

28. relativistic relativistic Chemical properties Chemical properties Chemical identification 114 →112→110 decays 14 12 Ca 20 Rn 86 Pu 94 Yu. Oganessian. Heavy Ion Physics in JINR. 28-th PAC meeting, June 19-20, JINR, Dubna

29. Compound Hg(Au) and 112(Au) Compound Hg(Au) and 112(Au) Reaction: 242Pu(48Ca,3n)287114[0.5s]→α→283112[3.6s] FLNR 2007 Yu. Oganessian. Heavy Ion Physics in JINR. 28-th PAC meeting, June 19-20, JINR, Dubna

30. 12th group of the Periodic Table Element 112 is a noble metal – like Hg

31. Chemical properties Chemical properties Periodic Table of the Chemical Elements

32. The study of the superheavy element’s atomic structure will show the limits of application of the Periodic law and will reveal new Periodic Table with taking into account the “relativistic” and other effects. It is also possible that these basic regularities can be revealed in the study of already synthesized elements with Z=111-118. But in any case, new experiments demand an increase in the productivity of superheavy nuclei by 10-50 times, at the expense of an increase in the ion beam intensity and creation of more fast methods.

33. Conclusion After 50 years of formation of heavy ion physics at the JINR the time has come to make a next step into the future Such steps have already been made in the leading nuclear centers of the world: RIKEN (Japan), GSI (Germany) GANIL (France)...... this club will definitely be extended by new members The JINR is most prepared for realizing its own scenario of heavy ion physics development; which seems to be very realistic and can be accomplished within short periods of time. We can hold the leading position for the Institute for the near and distant future in this field of physics.

34. Thank you very much for your attention