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Yu. Oganessian FLNR (JINR) PAC–meeting, June 22, 2009, Dubna

Theme: Synthesis of new nuclei and study of nuclear properties and heavy-ion reaction mechanism 03-05-1004- 1994/2009. Experimental activities and main results of the researches at FLNR (JINR). Yu. Oganessian FLNR (JINR) PAC–meeting, June 22, 2009, Dubna. INFN.

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Yu. Oganessian FLNR (JINR) PAC–meeting, June 22, 2009, Dubna

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  1. Theme: Synthesis of new nuclei and study of nuclear properties and heavy-ion reaction mechanism 03-05-1004-1994/2009 Experimental activities and main results of the researches at FLNR (JINR) Yu. Oganessian FLNR (JINR) PAC–meeting, June 22, 2009, Dubna

  2. INFN Pioneers BNL BNL INFN INFN RIKEN RIKEN CERN CERN GSI MSU GSI MSU Heavy ion accelerators RIB-Factory RIB-Factory A&M ANL JINR IPN LBL ORNL A&M LBL ANL IPN ORNL JINR Heavy Ion National Laboratories GANIL GANIL GSI GSI Heavy Ion Colliders RIB RIB RIB RIB RIB RIB RIB RIB RIB RIB Heavy ion physics: from the beginning to now…

  3. Nuclei close to and beyond the border line

  4. protons 50 50 82 28 20 50 p/n - transfer & fragmentation p/n - transfer & fragmentation /radioactive ion beams 28 8 2 beams of the neutron-rich projectiles: 3H(12.3y), 6He(0.8s) and 8He(0.12s)... 20 2 8 neutrons & target nuclei:1,2H,3H(12.3y),3,4He Heaviest nuclei Light nuclei

  5. Radioactive ion beams 0.8s 0.1s beams Shells in the light nuclei Shells in the light nuclei

  6. now 6He Dubna Radioactive Ion Beams 400-cm cyclotron radioactive ion beams low energy beam line ISOL Electron accelerator now 8He DIRECT 400-cm cyclotron DIRECT stable ion beams now 7Li

  7. Neutron correlations Neutron correlations

  8. Strangely enough, but all the combinations: 3H, 6He, 8He (beams) + 1H, 2H, 3H (targets) have been studied.

  9. strong shell effect in the “doubly-magic” nucleus evidence of shell structure 5730y discovery “di-neutron” in halo-nucleus 6He FLNR 2001 no shell effect was observed Be 2p-emission Unbound superheavy hydrogen structure

  10. 0.11s β+-2p emission Ne 2p-emission Be discovery “di-neutron” in halo-nucleus 6He FLNR 2001

  11. 6He Sub-barrier fusion of halo nucleus Sub-barrier fusion of halo nucleus neutron transfer 6He Pb 4He Pb

  12. Nuclear reactions induced by halo nuclei Nuclear reactions induced by halo nuclei “of-line” gamma measurements targets: Au, Pb Cross sections (mb) 6He-neutron transfer 4He-fusion 4He-neutron transfer 6He-fusion ECM- EB (MeV)

  13. Experimental scheme & conditions “in-beam” gamma spectroscopy Ю.Ц. Оганесян. «Тяжелые ионы в ЛЯР». Семинар, ЛЯР ОИЯИ, Дубна, 28 апреля 2008г.

  14. Heaviest nuclei

  15. Heaviest nuclei search for magic numbers 114 108 48Ca-beam 100 Pb-based fusion 184 Pb-based fusion & actinide target nuclei 162 152 82 126 protons neutrons Light nuclei

  16. New lands New lands New lands New lands Island of Stability 120 r cold fusion Pb + HI e b shoal m u 110 n hot fusion Act.+ 48Ca n o t peninsula o r P 100 continent 90 80 70 150 170 100 110 130 140 190 120 160 180 Neutron number Microscopic theory Island of Stability

  17. Reaction of Synthesis Fusion & fission

  18. 238U+48Ca 33MeV 208Pb+48Ca +58Fe 26MeV Cold fusion Act.+48Ca 21MeV +86Kr

  19. FLNR 1962 β-delay fission FLNR 1962 γ-rays fission isomers spontaneous fission quasi fission FLNR 1998► fission modes touching point neutrons 1940► fission from the excited state FLNR 1963►

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

  21. Z=120 252Fm 248Cf 238U 232Th 226Ra

  22. Search for Element 120 Search for Element 120 The sensitivity of experiment corresponds to σ=0.4 pb for detection of one event.

  23. Fusion Probability Fusion Probability Z=108 Z=108 48Ca+226Ra 136Xe+136Xe 132Sn+176Yb

  24. Decay Properties

  25. 226Ra Decay chains Decay chains 237Np 243Am 242Pu, 245Cm 117/293 117/294 244Pu, 248Cm 249Cf 115/289 115/290 2009-2010 113/285 113/286 249Bk +48Ca 111/282 111/281 T1/2= 320d Collaboration: FLNR (Dubna) ORNL (Oak-Ridge) LLNL (Livermore) IAR (Dmitrovgrad) Vanderbilt University (Nashville) 34 nuclides 109/277 109/278 Hs/270 σ4n≈10pb 10 s a 9.06 107/274 107/273 Sg/266 0.2 s 105/270 105/269 104/269 104/270 103/266 102/266 164 48Ca +

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

  27. With Z >40% larger than that of Bi, the heaviest stable element, that is an impressive extension in nuclear survival. Although the SHN are at the limits of Coulomb stability, shell stabilization lowers: the ground-state energy, creates a fission barrier, and thereby enables the SHN to exist. The fundamentals of the modern theory concerning the mass limits of nuclear matter have obtained experimental verification

  28. Size of SH-nuclei Size of SH-nuclei Geiger–Nutall relation Log Tα= C + D/√Qα based on invariable density of nuclear matter and nuclear size: R = r0·A1/3 perfectlyworks in the Region: 212Po-238U, where alpha-decay half-liveschanged more than 1025 times!

  29. available for chemical studies Act.+48Ca Superheavy nuclei aren't exception to this rule Cold fusion

  30. Chemical properties

  31. Hg Tl Pb Bi Atomic properties Atomic properties

  32. Element 112 is a noble metal – like Hg more and more inert? room temperature Periodic Table of Elements Periodic Table of Elements

  33. transport & on-line chemistry transport & off-line chemistry

  34. Half-lives of nuclei with Z ≥ 110 Half-lives of nuclei with Z ≥ 110 available for chemistry & mass separation “on line” “gas catcher” “in flight” N=162 Act. + 48Ca

  35. GAS CATCHER GAS CATCHER rotating target H2+B beam separating window RECOILS q=qeq entrance window RF pumping q=1+He beam RF stopping volume RF+E E acceleration beam of high quality pumping Guy Savard from Argonne National Laboratory

  36. 2009 / 2010 • Experiments on synthesis of the isotopes of element 117 • in the reaction 249Bk + 48Ca. • a) Gas-filled separator • b) Chemistry: on-line Z=113 / off-line Z=105 • up to July 2010 Cyclotron U-400 2. Studies of 2p-emission from 6Be in the charge – exchange reaction 6Li → 6Be with ACCULINA – separator Cyclotron U-400M 3. First experiments with on-line MASHA separator Low energy beam line on Cyclotron U-400M

  37. 110 scientist (16 doctors of science and 48 PhD) during next 6 years will take part in the new theme “Synthesis and properties of nuclei at the stability limits” (2010 / 2016) Thank you !

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