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  1. copernicium 112 roentgenium 111 darmstatdium 110 109 meitnerium 108 hassium 107 bohrium 2012SHN Superheavy Elements – an Island on Quantum Mechanical Grounding Dieter Ackermann GSI Helmholtzzentrum für Schwerionenforschung GmbH Lanzhou, August 10th 2012

  2. The Region of Superheavy Elements - GSI/SHIP achievements and outline • SHE - synthesis • confirmation of “hot fusion” decay patterns • hunt for the heaviest • SHE – nuclear structure studies • decay spectroscopy • trends along isotone chains • K-isomers (270Ds) • SHE – future strategy • FUSHE 2012 184 162 120 152 112 copernicium 114 111 roentgenium 110 darmstatdium 109 meitnerium 108 hassium sphericalshell-stabilised superheavy nuclei 107 bohrium 108 discovered at SHIP new or improved decay data Eshell deformed shell-stabilised superheavy nuclei Calc.: A. Sobszewiski

  3. Synthesis and Identification of SHE at SHIP n 208Pb 70Zn 277112 277112 277112 CN 11.45 MeV 280 s 273110 11.08 MeV 110  s 269Hs 9.23 MeV 19.7 s 265Sg 4.60 MeV (escape) 7.4 s 261Rf known 8.52 MeV 4.7 s 257No 8.34 MeV 15.0 s Date: 09-Feb-1996 Time: 22:37 h 253Fm kinematic separation in flight identification by - correlations to known nuclides

  4. “Hot Fusion” Studies - 48Ca (et al.) Induced Reactions on Actinide Targets 184 162 120 112 copernicium 114 111 roentgenium 110 darmstatdium 109 meitnerium 108 hassium 107 bohrium 108 discovered at SHIP new or improved decay data „Dubna challenge“ Eshell non connected decay chains Calc.: A. Sobszewiski

  5. The "Dubna Challenge"- 48Ca + 248Cm  296116* at GSI 293116 CN 293116 293116 CN CN 10.503 MeV 29 ms 289114 10.559 MeV 55 ms 10.54 MeV 89 ms 289114 289114 10.029 MeV 406 ms 285Cn 9.81 MeV 3.9 ms 9.813 MeV 118 ms 285Cn 285Cn 9.707 MeV 5.8 s 281Ds FLNR 9.100 MeV 5.8 s 9.110 MeV 66 s 281Ds 281Ds 9.315 356 ms 277Hs 197 MeV 16.5 s 226 MeV 6.0 s 210 MeV 49 s 5 events Yu.Ts. Oganessian, J. Phys. G 34 (2007) R165 02-July-2010, 01:07 h; chain 1 10.06 MeV, 6.3 mm, strip 4 08/09-July-2010, chain 6 21 MeV, 11.4 mm, strip 8 tentative assignment 48Ca + 248Cm => 293116 + 3n

  6. The "Dubna Challenge"- 48Ca + 248Cm  296116* at GSI 02-July-2010, 01:57 h; chain 2 8.96 MeV, 10.4 mm, strip 4 03-July-2010, 20:01 h; chain 3 18 MeV, 27.4 mm, strip 2 292116 292116 292116 292116 292116 CN CN CN CN CN 10.63 MeV 76 μs 10,6 MeV (stop + box) 11.6 ms 1.4 MeV (escape) 28.8 ms 10,66 MeV 26 ms 2,75 MeV (escape) 53.3 ms 288114 288114 288114 288114 288114 10.0 MeV (stop + box) 72 ms 9.91 MeV 1.17 s 9.90 MeV 1.3 s 1.8 MeV (escape) 252 ms 9.93 MeV 993 ms 284Cn 284Cn 284Cn 284Cn 284Cn 197 MeV 269 ms 172 MeV 50 ms 185 MeV 25 ms 190 MeV 130 ms 195 MeV 121 ms FLNR 07-July-2010, 00:10 h; chain 4 22 MeV, 24 mm, strip 15 07-July-2010, 09:01 h; chain 5 21 MeV, 28 mm, strip 12 6 events Yu.Ts. Oganessian, J. Phys. G 34 (2007) R165 48Ca + 248Cm => 292116 + 4n

  7. The "Dubna Challenge"- 48Ca + 248Cm  296116* at GSI 3n [293] 4n [292] Yu.Ts. Oganessian, J. Phys. G 34 (2007) R165 FLNR GSI

  8. Confirmation of FLNR Results - Summary LBNL BGS 286114 287114 SHIP 283112 293116 292116 289114 288114 BGS TASCA SHIP a SF shell- correction [MeV] b+/EC b- 7 6 5 4 3 120 L. Stavstera, Phys. Rev. Lett.103, 132502 (2009). Z GSI SHIP 118 2 ms 118 112 ms 10 ms GSI SHIP 116 30 ms 6 ms 20ms 50ms 116 115 115 30 ms 0.1 s 230 ms 320 ms 115 114 114 0.1 s 0.5 s 0.6 s 3 s 114 • achievements • impressive body of decay data • confirmation at different laboratories • first promising chemistry results for 112/114 • remaining challenges • unambiguous Z(A) identification • extension towards higher Z • localisation of "island of stability" 113 113 200ms 28,3 s 1.2 s 0.1 s 0.5 s 73ms GSI TASCA 112 112 600ms 1 ms 4 s 0.1 s 30 s 4.2ms 0,74 s 111 Rg 6 ms 0.2 s 4 s 38 s 3 ms 110 56ms 110 Ds 10 s ? 200ms 100ms 170ms 0.2 s 109 Mt 2 ms 30ms 5 ms 0.44 s 10ms 0.8 s 11 s 108 0.2 s 108 Hs ? 0.5ms 2 ms 2 ms 50ms 14 s 4 s 3 s decay mode 61 s 107 Bh 10ms 0.1 s 1 s 1 s 1 s 17 s ? 10 s 1.3 min 106 Sg 3 ms 0.5 s 4 ms 0.1 s 7 ms 1 s 7 s 21 s 2 m 105 105 1.6 s 1.5 s 4 s 0.5 s 1.5 s 2 s 30 s 30 s Db 1.6 s 1.2 h 33,4 h 22 m 29 h 185 1,3 h 104 20ms 1.6 s 6 ms 4 s 10ms 3 s 20ms 1 m 2 s 15 m Rf 50ms 184 103 0.4 s 0.6 s 10 s 20 s 30 s 0.5 s 4 s 6 s 3 m Lr 40 m 4 h excerpt chart of nuclides: courtesy of Ch.E. Düllmann 102 No 50ms 6 ms 1 s 3 s 2 m 1 m 3 m 3 s 30 s 1 ms 1 h 0.1 s 5 ms 101 0.2 s Md 1 s 7 s 30 s 1 m 4 m 2 m 6 m 30 m 30 m 1 h 6 h 50 d 1 h 30 d 100 4 s Fm 1 s 40 s 40 s 3 m 30 m 5 h 25 h 3 d 3 h 20 h 3 h 100d 400ms 1.5 s 99 37 s Es 1 m 8 m 5 m 30 m 2 h 8 h 33 h 1 yr 20 d 1 yr 40 d 30 m 8 d 180 98 Cf 45 m 35 h 3 h 1 yr 0.4kyr 13 yr 0.9kyr 3 yr 15 d 60 d 1 h 12 m 10 m 19 m N 160 150 152 155 162 165 170 175 145

  9. Hunt for the heaviest- towards element 119,120 at SHIP and TASCA V. Zagrebaev, TAN 2011 302120* 299120* • SHIP • 64Ni + 238U  302120*2007/2008120 days / lim < 0.09 pbarn • 54Cr + 248Cm  302120* spring 201136 days / lim < 0.56 pbarn • 256Rf • with JUROGAM, • RITU and GREAT • 450 h beam on target • 17 nbarn • 29 particle nA • P. Greenlees et al. • September 2011 299119* Requirement: months to years of beam time @ 0.5 - >1 particle μA • TASCA • 50Ti + 249Cf  299120*August-October 2011 40 days / lim < 0.2 pbarn • 50Ti + 249Bk  299119*presently running

  10. Nuclear Structure of SHE - Decay Spectroscopy at SHIP/TASCA  emission CE emission  emission x-ray emission • isomer surviving separation  emission •  emission after  decay • CE for highly converted transitions + X-ray emission evaporation residue after separation

  11. Nuclear Structure of SHE - Decay Spectroscopy at SHIP/TASCA F.P. Heßberger et al, EPJ A 30, 561 (2006) • inclusive measurement • ER, 's, 's and e- • clean • particle discrimination • ER-- correlations • highly efficient • close geometry • stopped source (e.g. SHIP, TASCA...) high eff.   15%

  12. Nuclear Structure of Heavy Nuclei- Single Particle Levels and Deformation protons neutrons 184 162 114 108 152 102 100 142 96 134 126 82

  13. Nuclear Structure of Heavy Nuclei- Single Particle Levels and Deformation 7/2-[514] f5/2 7/2+[624] d5/2 1/2-[521] f7/2 j15/2 i13/2 3/2-[521] 9/2-[734] g9/2 h9/2 7/2+[633] 1/2+[631] protons neutrons 184 162 114 108 152 102 100 142 96 134 126 82

  14. Nuclear Structure of the Heaviest Nuclei:- Production Rates reaction σ/nbarn Ibeam/pμA countrate . 208Pb(48Ca,2n)254No 2000 1 15000 /h (at RITU/Jyväskylä 200 /h) 206Pb(48Ca,2n)252No 430 1 3300 /h 206Pb(48Ca,3n)251No 25 1 200 /h 209Bi(40Ar,2n)247Md 7 3 80 /h 208Pb(54Cr,1n)261Sg 2 1 15 /h 207Pb(64Ni,1n)270Ds 0.013 0.5 1 /d

  15. Nuclear Structure of the Heaviest Nuclei:- Isomeric states: 254No 208Pb(48Ca,2n)254No F.P. Heßberger et al., Eur. Phys. J. A 43, 55-66 (2010) R.D. Herzberg et al., Nature 442, 896 (2006); S.K. Tandel et al., Phys. Rev. Lett. 97, 082502 (2006)

  16. 270Ds and its Decay Products- 1st experiment in 2000 (S. Hofmann et al., Eur. Phys. J. A 10, 5 (2001)) 270Ds266Hs (6 chains) chain# 1, 3 and 5 chain# 2 chain# 8 chain# 7 266Hs262Sg (8 chains) chain# 1-8 262Sg decay (8 chains) chain# 1-8 8+ 6+ Experiment: S. Hofmann et al. Theory: rotational levels: A. Sobiczewski et al. K-isomers S. Cwiok et al.

  17. K-isomer in 270Ds- Theory Predictions: quasi particle excitation neutrons 162 162 162 Fermi level [725]11/2- [725]11/2- [725]11/2- [615]9/2+ [615]9/2+ [615]9/2+ [613]7/2+ [613]7/2+ [613]7/2+ g.s. 1.31 MeV I = 9- 1.34 MeV I = 10- 270Ds: Z=110 N= 160 ? S. Ćwiok, et al. HFB

  18. Decay Chain of 270Ds from 64Ni+207Pb- Results from October 2000 and Possible Extension SHIPTRAP August 2008 ?

  19. 2010: Observed types of decay chains I- ER-α-α-sf a) ER-α-α-sf 15 chains

  20. 270Ds - 270Ds α-decay • 26 decay chains (270Ds: 25, 271Ds:1) • new spectroscopic data * * T1/2 from S. Hofmann et al., Eur. Phys. J. A 10, 5 (2001)

  21. 2010: Observed types of decay chains II- ER-α-sf b) ER-α-sf a) ER-α-α-sf 8 chains  sf(266Hs) = 24% 15 chains

  22. 270Ds - 266Hs sf-branch • 26 decay chains (270Ds: 25, 271Ds:1) • new spectroscopic data * new fission branch in 266Hs * * T1/2 from S. Hofmann et al., Eur. Phys. J. A 10, 5 (2001)

  23. 2010: Observed types of decay chains III- ER-α-α-α-sf b) ER-α-sf c) ER-α-α-α-sf a) ER-α-α-sf 8 chains  sf(266Hs) = 24% 2 chains  α(262Sg) = 6% 15 chains

  24. 270Ds - News III – 262Sg α-branch  link to 254No • 26 decay chains (270Ds: 25, 271Ds:1) • new spectroscopic data * new fission branch in 266Hs * α-decay link 262Sg  258Rf * • J. M. GATES et al. PRC 77, 034603 (2008) * T1/2 from S. Hofmann et al., Eur. Phys. J. A 10, 5 (2001)

  25. Decay details- time distributions Run 197 - experiment 2000 Run282 - experiment 2010 105 ms

  26. 270Ds Decay Scheme • 270Ds: • 12 g.s. decays • 13 isomer decays - 2 γ‘s: 175/741 keV • (in 2000: 3:3 + 1 γ) • chain 8: • Eα 200-300 keV lower • 266Hs: • 16 g.s. decays • 1 isomer decay • with a 332 keV γ-ray • chain 8: • Eα 200 keV higher • Ev = 332 keV • 262Sg: • α decay observed for the first time (1 full E, 1 escape) 6- 8+ 6+ 10- 9- 10- 10- 8+ 9- 10- 10+ 8+ 6+ 7- 4- 9- 10+ 9- 8+ 9- 10- 9- 10- 8+ 6+ 7- 6+ 4+ 5+ 5- 7- 9- 10- 332 kev Calculations: HFB: S. Cwiok, et al. PES: F.R. Xu, et al. PRL 92, 252501 (2004) TCSM: G.G. Adamian et al., PRC 81, 024320 (2010)

  27. Energy Density Functional Calculations - Vaia Prassa, Dario Vretenar et al. 6- 8+ 6+ 10- 9- 10- 10- 8+ 9- 10- 10+ 8+ 6+ 7- 4- 9- 10+ 9- 8+ 9- 10- 9- 10- 8+ 6+ 7- 6+ 4+ 5+ 5- 7- 9- 10- Tg.s. Tisomer 332 kev Calculations: HFB: S. Cwiok, et al. PES: F.R. Xu, et al. PRL 92, 252501 (2004) TCSM: G.G. Adamian et al., PRC 81, 024320 (2010)

  28. Energy Density Functional Calculations - Vaia Prassa, Dario Vretenar et al. S. Ćwiok et al., NATURE, 433 (2005) HFB + SLy4

  29. Summary - Achievements • ground state, decay and structure properties up to Z=110 • α-γ coincidences (total: 4) • fission branch in 266Hs • experimental mass for 270Ds • new K-isomer 266 Hs

  30. SHE Synthesis and Nuclear Structure of SHE - Roadmap/Long Term Possible GSI acc. schemes: New M/q spectrometer – separator for SHE material science/ISL high charge cw-injector target ECR 1 SIS beam separator (e.g. velocity filter) SHIP cw warm cw cold Possible Solution: S3 @ SHIP beam M/q spectrometer MUCIS MEVVA ECR 2 X1 TASCA HSI TD X1 TASCA SHE Exp. HSI TD UNILAC PB Penning • efficient beam separation • high transmission • M/q separation • highly efficient particle and photon detection high charge cw-injector ISL particle and phonon detection array • nuclear structure studies  single particle states/level density gap • reaction mechanism systematics (transfer, fission, incomplete fusion, spin distribution, ...) • efficiency upgrade  DC accelerator • mass measurement  Ebind • mass determination (A(Z) identification)  new separator/spectrometer • employment of all available technology and methods (ER-α-γ correlations, chemistry, traps, mass determination, ...) • “rare isotopes”? • yes for systematic investigations • maybe(???) for SHE synthesis (low beam intensity!!!) •  localisation of the region of spherical shell-stabilized SHE

  31. The ECOS Network Activity in theENSAR framework of the EU FP7 program has among others with its Task 2 the objective to promote synergies in the field of Super-Heavy Element (SHE) research, described as follows: "For this task ECOS is aiming for bringing together the groups with research activities on SHE using high-intensity ion beams for an exchange of new ideas and techniques related to the use of very high intensity stable beams. In particular, Task 2 will propose an optimisation of resources (beam time, target technology, detectors) in the field of SHE research among TNA facilities." The ENSAR-ECOS Workshop on FUture Super-Heavy Element Strategy – FUSHE 2012 is one very important milestone in this process. It will provide a forum for the SHE community to discuss and define the future strategyto reach the common goal – the establishment and investigation of the region of spherical shell-stabilised super-heavy nuclei – the so called “Island of Stability”.

  32. FUSHE 2012 May 13th – 16th 2012 • Workshop Structure and Goal • The workshop - attended by  90 participants from all institutions involved in SHE research worldwide – was organised in 7 x ½-day sessions with a strong emphasis on discussions including Theory, Experiment and Instrumentation arguments • The sessions were organised as a combination of invited talks followed by a topical discussion for the subjects: • SHE Synthesis • Nuclear Structure of SHE • Chemistry • Atomic Physics and Alternative Approaches • As a main deliverable of the workshop a paper laying out the – near and far -future strategy in SHE research will be produced and published

  33. The SHIP Collaboration D.A., M. Block, H.G. Burkhard, Ch. Dröse, M. Dworschak, F.P. Heßberger, S. Hofmann, W. Hartmann, A. Hübner, B. Kindler, J. Khuyagbaatar*, I. Kojouharov, B. Lommel, R. Mann, J. Maurer, E. Minaya, J. Steiner Gesellschaft für Schwerionenforschung (GSI) D-64220 Darmstadt, Germany A.G. Popeko, A.V. Yeremin Flerov Laboratory of Nuclear Reactions, JINR Ru-141 980 Dubna, Russia S. Antalic, S. Šaro Department of Nuclear Physics, Comenius University SK-84248 Bratislava, Slovakia M. Leino, J. Uusitalo Department of Physics, University of Jyväskylä FIN-40351 Jyväskylä, Finland V.F. Comas, J.A. Heredia Higher Inst. of Technologies and Appl. Sciences Havana 10600, Cuba K. Nishio Japan Atomic Energy Research Institute Tokai, Ibaraki 319-1195, Japan R. Grzywaczb, K. Miernikc, J.B. Roberto, K.P. Rykaczewski ORNL Oak Ridge band Univ. of T ennessee cand Univ. of Warsaw K. Eberhardt, J. Runke, P. Thörle-Pospiech, N. Trautmann University Mainz, Germany photograph by Gabi Otto