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Yuri Oganessian Flerov Laboratory of Nuclear Reactions Joint Institute for Nuclear Research

SHE in JINR. Yuri Oganessian Flerov Laboratory of Nuclear Reactions Joint Institute for Nuclear Research. 109 th Session of the JINR Scientific Council Feb.17-18, 2010, Dubna. Synthesis of SHE with 48 Ca-induced reactions 10 years. Decay chains.

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Yuri Oganessian Flerov Laboratory of Nuclear Reactions Joint Institute for Nuclear Research

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  1. SHE in JINR Yuri Oganessian Flerov Laboratory of Nuclear Reactions Joint Institute for Nuclear Research 109thSession of the JINR Scientific Council Feb.17-18, 2010, Dubna.

  2. Synthesis of SHE with 48Ca-induced reactions 10 years

  3. Decay chains Decay chains Talk at the Meeting of RAS, Nov.,2000 244Pu, 248Cm +48Ca Z=116 0.06 s 2.5 s 114 114 0.5 min 112 0.7 ms 11s 170μs 110 184

  4. Confirmations2007-2010 Yu. Oganessian “SHE in JINR” 109-th Session of the SC of JINR, Feb. 17-18, 2011, Dubna

  5. 6 new superheavy elements 118 117 116 2010 115 114 Yu. Oganessian 2010 113 112 249Bk +48Ca 111 T1/2= 320d 110 109 48 new isotopes 108 107 106 105 104 Yu. Oganessian “SHE in JINR” 109-th Session of the SC of JINR, Feb. 17-18, 2011, Dubna

  6. Total evaporation residues cross sections (pb) 100000 10000 Cross sections Cross sections 1000 100 SHE 10 48Ca-induced reactions 1 Cold fusion factor ~300 0.1 0.01 100 105 110 115 120 Atomic number

  7. TechnicalAchievements &Collaborations

  8. Search for Element 116 in248Cm +48Ca reaction Search for Element 116 in248Cm +48Ca reaction “in flight” separation chemical separation GSI, Darmstadt, Germany* LBL, UC Berkeley, CA Univ. of Mainz, Germany LANL, Los Alamos, NM EIR, Würenlingen, Switzerland 1985 292116 293116 FLNR, Dubna LLNL, Livermore, CA 2000

  9. TARGETS The neutron-rich isotopes of the Actinides was produced at ORNL (USA) by irradiation: of Cm and Am targets in each campaine for approximately 250 days by thermal-neutron flux of 2.5  1015 n/cm²·s in the HFIR (High Flux Isotope Reactor).  Yu. Oganessian “SHE in JINR” 109-th Session of the SC of JINR, Feb. 17-18, 2011, Dubna

  10. BEAMS Beam dose: 2.4·1019 0.3%

  11. DETECTORS Dubna Gas-Filled Recoil Separator Dubna Gas-Filled Recoil Separator From the characteristics of the DGFRS, it follows that with a 48Са-beam dose of 3∙1017 realized for 1 day the observation of one decay event corresponds to the production cross section of about 10 pb. beam 48Ca target

  12. Decay Properties of SHE:expected & obtained

  13. Alpha-decay Alpha-decay

  14. Spontaneous fission half-lives Spontaneous fission half-lives Actinides Trans-actinides Superheavy nuclei 48Ca-induced reactions

  15. With Z >40% larger than that of Bi, the heaviest stable element, • we see an impressive extension in nuclear survival. • Although SHN are at the limits of Coulomb stability, • shell stabilization lowers ground-state energy, • creates a fission barrier, • and thereby enables SHN to exist. • . The fundamentals of the modern theory concerning the mass limits of nuclear matter have obtained experimental verification Yu. Oganessian “SHE in JINR” 109-th Session of the SC of JINR, Feb. 17-18, 2011, Dubna

  16. Consequences

  17. Electronic structure of SHE-atoms Nuclear theory Atomic Physics Search for new shells Chemical properties of the SHE Chemistry Nuclear structure and decay properties of the SHN Nuclear Physics protons → A=294 Search for SHE in Nature Astrophysics neutrons → Yu. Oganessian “SHE in JINR” 109-th Session of the SC of JINR, Feb. 17-18, 2011, Dubna

  18. Decays & Spectroscopy of Super heavy Nuclei

  19. 6 new superheavy elements 118 117 116 protons 115 114 Previously known nuclei from cold Fusion reactions 113 112 111 110 It is questionable that “filling in empty spaces” would give us significant information about nuclear structure of SHE 109 48 new isotopes 108 107 106 105 104 neutrons

  20. Cross sections Cross sections σxn ~ (Γn / Γf)x; х –number of evaporated neutrons (Γn / Γf) ~ exp(Bf – Bn) / T Bf = BfLD + ΔEShell 0 SHN Hot fusion Ex=45-50 MeV

  21. Spontaneous fission of heavy and super heavy elements 118 117 116 115 114 Z=110-114 N=170-172 TSF= 0.001-10s 113 112 111 110 109 108 107 Z=104-106 very neutron-rich nuclei N=162-166 T1/2 = 104-105s 106 105 104

  22. Z1 ≈ Z2 = 50-54 N1 = N2 = 82 rel. units Yield (rel. units) QF = 268 MeV E. K. Hulet, et al., P.R. C40, 770 (1989)

  23. “on line” “gas catcher” N=162 Act. + 48Ca Yu. Oganessian “SHE in JINR” 109-th Session of the SC of JINR, Feb. 17-18, 2011, Dubna

  24. ε=0.5 mm·mrad Experimental l technique ΔE=0.5 eV FLNR /ANL beam 48Ca target

  25. Superheavy Atoms Chemistry of the SHE

  26. (finite size) Zmax≈173 Heaviest atoms in QED (point charge) SHE Hg Zmax=1/α=137 where α is fine-structure constant

  27. rmax- principal maximum of the wave function of the outermost orbital Zmax

  28. FLNR / PSI chemical compound (Au·Hg) (Au·112) R. Eichler et al., Nature 447 (2007) 72

  29. SHE ion charge exchange in the gas-target Beam of SHE with variable energy Yu. Oganessian “SHE in JINR” 109-th Session of the SC of JINR, Feb. 17-18, 2011, Dubna

  30. Theoretical Models Nuclear forces Macro – Microscopic Model (MMM) Hartry – Fock – Bogolubov (HFB) Relativistic Mean Field (RMF)

  31. 251Cf HFB +50Ti +48Ca MMM MMM Yu. Oganessian “SHE in JINR” 109-th Session of the SC of JINR, Feb. 17-18, 2011, Dubna

  32. Strategy

  33. Gain factors for production of Super-heavy nuclei 2.5pμA Current experiments Yu. Oganessian “SHE in JINR” 109-th Session of the SC of JINR, Feb. 17-18, 2011, Dubna

  34. Feb.17, 2011, 1:59 AM. From ORNL, USA Dear Yuri We have received authorization from DOE for production of Bk-249 for the upcoming experiments at Dubna and at GSI. Your letter and your trip to DOE were very helpful in securing approval. Thank you for your support. We anticipate that the material will be ready for shipment later this year in the December-January timeframe. A more detailed schedule will be forthcoming. We look forward to working with you on these exciting experiments. With best regards, Jim

  35. Thank you

  36. 2011 - 2017 Yu. Oganessian “SHE in JINR” 109-th Session of the SC of JINR, Feb. 17-18, 2011, Dubna

  37. 2011 - 2016

  38. P. Moller et al., Phys. Rev., C79, 064304 (2009) spherical ~8pb ▼ ▼ ▼ ▼ ▼ ▼ ▼ ▼ ▼ ▼ ▼ Z=117 ▼ ▼ ▼ ▼ ▼ Z=112 ▼ deformed ≤0.6pb ▼ Yu. Oganessian “SHE in JINR” 109-th Session of the SC of JINR, Feb. 17-18, 2011, Dubna

  39. more and more inert? Periodic Table of Elements Periodic Table of Elements Yu. Oganessian. Colloquium at MIT, Feb.10, 2011

  40. 249Bk 237Np , 243Am , From reactions: 48Ca + SF SF Z=104 N=162 164 166

  41. 120 120 120 114 114 114 120 120 120 114 114 114 Z=114 / N=184 251Cf + 48Ca → 296(118) +3n→ 251Cf + 50Ti → 298(120) +3n→ M. Bender et al., PRC60 & PLB515 Yu. Oganessian “SHE in JINR” 109-th Session of the SC of JINR, Feb. 17-18, 2011, Dubna

  42. Opportunities for future research Island of Stability 1µs 1s 1h 1My 1y 120 Shoal 110 Peninsula Protonnumber 100 Sea of Instability 90 Continent 80 70 150 170 100 110 130 140 190 120 160 180 Neutron number Oganessian, ENAM (2008) New targets New beams New elements New isotopes Higher neutron numbers New physics New chemistry

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