Summary Experiment R.-D. Herzberg Ch.E. Düllmann Discovery of a new element is as fascinating to the public as landing on the moon (or Mars) M. Stoyer “The question weʼre trying to answer is, ʻDoes the periodic table come to an end, and if so, where does it end?ʼ ” Kenton Moody -- LLNL$ Yu. Oganessian → Electronic structure Nuclear theory Atomic Physics of SHE-atoms Search for new shells protons Chemical properties of the SHE 120 Chemistry SHE Nuclear structure and decay SHE -7 properties of the SHN 110 Nuclear Physics Search for SHE -6 -5 in Nature -4 Astrophysics 100 -5 No -3 -4 -3 -2 U 90 -4 Th -2 Bi Pb -14 neutrons → 80 Oganessian 2012 Yu. 120 130 140 150 160 170 180 190 Yuri Oganessian. “Synthesis of SH-nuclei” FUSHE 2012, May14, 2012, Weilrod, Germany Scienfic Quesons • What is the heaviest element we can make? • What is the heaviest nucleus we can make and what are the best methods to do so? • What is the nuclear structure in the heaviest nuclei? • What are the chemical and atomic properNes of the heaviest elements and is chemical periodicity altered as relavisNc effects become more important? • Are there astrophysical scenarios in which SHEs are produced or does fission limit the producNon of SHEs? Do the heaviest elements exist in nature? • (How) Can we produce weighable quanNNes on earth? What is the heaviest element? • Where is the island of stability? • What are the best methods to create them? • What determines their survival and stability? • What are their properNes? Yu. Oganessian 130 We are here! Need to get here! β-stability 287Fl 277Cn 291Lv Island of stability of SHE 200 210 Yuri Oganessian. “Synthesis of SH-nuclei” FUSHE 2012, May14, 2012, Weilrod, Germany Modern Periodic Table of Elements Should we pick up U+U studies again? In a fixed-target or in a collider experiment? ? Z=173 V. Pershina New Elements / Isotopes Observed are mainly integral quanNNes: • The atom itself! • Decay mode • Half-life • Q-value or TKE A rich and growing body of data! Creaon • ReacNon mechanisms? • Best target/beam combinaons? • How reliably is theory predicNng cross secons? Superheavies: V. Zagrebaev 1. Theoretical models of formation dynamics Experimental possibliNes(the problems to be solved) • Fusion reactions (new SH elements and isotopes) • Transfer reactions (new neutron-rich SH nuclei) • Neutron capture (SHE in nature) 2. SHE experiments (what could be really done within the next few years) Valeriy Zagrebaev Flerov Laboratory of Nuclear Reactions, JINR, Dubna for “Future of Super Heavy Elements”, May 14, 2012, Weiltal, Germany 10 New element discovery has progressed steadily since the 1700’s M. Stoyer On average, just under 20 elements have been On average, about 4 discovered every half- elements have been century$ discovered every decade$ 100000 CrossCross sectionssections 10000 1000 Yu. Oganessian 2012 Yu. 100 ?SHE 10 48Ca-induced factor ≥ 104 reactions 1 Cold fusion 0.1 ) pb Total evaporation residues cross sections ( 0.01 100 105 110 115 120 Yu. Oganessian Atomic number Making new elements ZBeam Beam Target Asymmetry E*@BBass E120 22 50Ti 249Cf 31.7 23 51V 249Bk 35.9 24 54Cr 248Cm 33.0 25 55Mn 243Am 34.5 26 58Fe 244Pu 33.9 27 59Co 237Np 32.9 28 64Ni 238U 27.3 Similar argumentsStrategic for E119aspect: hint at 50Ti +249BkThe as thecommunity preferred depends reaction on access to transuranium isotopes in mg quantities! Ch.E. Düllmann – DPG Frühjahrstagung 2012 – Johannes Gutenberg-Universität Mainz – 19.-23. März 2012 Transuranium Nuclide Production Paths Advanced Production Fm254 Fm255 Fm256 Fm257 Methods for Bk-249 and 100 Fm Heavier Isotopes α α SF α, (n,f) Es253 254Es254 Es255 99 Es - C.W. Alexander (ORNL) α αEs, β ,EC β- Cf249 Cf250 251Cf251 Cf252 Cf253 Cf254 98 Cf α, (n,f) α αCf, (n,f) α, SF β-, (n,f) α, SF 249Bk249 Bk250 Bk251 97 Bk Bkβ- β- β- Cm242 Cm243 Cm244 Cm245 Cm246 Cm247 Cm248 Cm249 Cm250 248 96 Cm - α α, (n,f) α α, (n,f) α α, (n,f) Cmα, SF β- α, β ,SF Am241 Am242 Am243 Am244 Am245 Am246 Superheavy element 95 Am - α β ,EC,(n,f) α β- β- β- collaboration meeting Pu240 Pu241 Pu242 Pu243 Pu244 Pu245 Pu246 at LaGuardia Marriott 94 Pu α β-, (n,f) α β- α β- β- Jan. 19-20, 2012, New York Yu. Oganessian Fusion evaporation reactions H. Savajols 48 q High intense stable beams beyond Ca Fusion reactions to Z=120 50 249 295,296 Ti + Cf à 120 + 3,4n 54Cr + 248Cm à 298,299120 + 3,4n 58Fe + 242Pu à 296,297120 + 3,4n Dubna : σ< 0.4pb 64Ni +238U à 298,299120 + 3,4n GSI:σ<0.1 pb 88Sr + 208Pb à 294,295120 + 1,2n V. Zagrebaev et al. 12 Today: I ≈ 5×10 /s è σlimit≈0.1pb 14 Future: I ≈ 10 /s è σlimit≈1 fb Cross sections: current predictions from theory Fe+Pu Ti+Cf Zagrebaev (Myers/Swiatecki) 4 Cr+Cm Ni+U Siwek-Wilczynksa (Muntian) 10 Adamian (Möller) Adamian (Liran) Liu (Möller) 3 Nasirov (Muntian) 10 Kuzmina (Kuzmina) Wang (Muntian) Exp 102 Best reaction: 50Ti+249Cf σ predicted: ~40 fb – 1 pb 101 100 cross section / fb Asymmetric (More) symmetric Asymmetry Ch.E. Düllmann – DPG Frühjahrstagung 2012 – Johannes Gutenberg-Universität Mainz – 19.-23. März 2012 50Ti+249Cf Excitation Function 1000 3n exit channel 4n exit channel σ(48Ca+249Cf→E118) ~500 fb Liu + Bao ('09) A100 lesson: (Möller 1995; Möller FRDM) Möller It is REALLY necessary to add error bars! In y ANDWang in x!et al. ('11)Liu (Liu 2011; Liu WS3) Swiatecki A question: Zagrebaev etSwiatecki al. ('08) (Myers 1996; TF) Muntian / fb σ Muntian Will10 a dedicated SHE supercomputer help? Siwek-Wilczynska Möller ('10) (Muntian 2003) Möller Nasirov et al. Munitan ('11) Muntian A personal note: (Möller 1995; FRDM) Möller Möller We are speaking about an element only 2 units ofNasirov Z heavier et al. ('11) (Muntian Liran 2003) 1than the heaviest reported one! Given the differences Liran Adamian et al. ('09) among the models, how should we reliably estimate (Möller the 1995; FRDM) number260 of elements270 accessible280 290 in the next300 x years?Adamian et al. ('09) (Liran 2001) E / MeV Lab Ch.E. Düllmann – DPG Frühjahrstagung 2012 – Johannes Gutenberg-Universität Mainz – 19.-23. März 2012 50Ti+249Bk Excitation Function 1000 Agreement 1: 4n is larger than 3n 3n exit channel 4n exit channel Agreement 2: Position100 (in E) of maximum Liu (Möller) Liu (Möller) Wang (Liu) Wang (Liu) Zagrebaev (Myers) Zagrebaev (Myers) Siwek-Wilczynska (Muntian) / fb σ Liu + Bao Siwek-Wilczynska (Muntian) 10 (Möller 1995; FRDM) Wang et al. (Liu 2011; WS3) Zagrebaev + Greiner (Myers 1996; TF) 1 Siwek-Wilczynska (Muntian 2003) 260 270 280 290 E / MeV Lab Ch.E. Düllmann – DPG Frühjahrstagung 2012 – Johannes Gutenberg-Universität Mainz – 19.-23. März 2012 The TASCA Element 119 Collaboration GSI Darmstadt (D) D. Ackermann, M. Block, F.P. Heßberger, A. Hübner, E. Jäger, B. Kindler, J. Krier, N. Kurz, B. Lommel, J. Runke, March 6: B. Schausten, J. Steiner, A. Yakushev Arrival of 249Bk in EE / Ion source / Accelerator staff Mainz Univ. Mainz (D) Ch.E. Düllmann, K. Eberhardt, S. Klein, J.V. Kratz, C. Mokry, D. Renisch, P. Thörle-Pospiech, N. Trautmann, N. Wiehl MarchHIM 23: Mainz (D) L.-L. Andersson, J. Even, J. Khuyagbaatar, V. Yakusheva ArrivalORNL of Targets / UT Knoxville at (USA) R. Grzywacz, D. Miller, J. Roberto, K. Rykaczewski GSI Vanderbilt U (USA) J.H. Hamilton LBNL / UC Berkeley (USA) N. Esker, J.M. Gates, K.E. Gregorich, H. Nitsche, G.K. Pang LLNL (USA) J.M. Gostic, R.A. Henderson, K.J. Moody, D.A. Shaughnessy April 12: Lund Univ (S) C. Fahlander, U. Forsberg, P. Golubev, D. Rudolph Mounting Targets in Univ. Liverpool (UK) D.M. Cox, R.-D. Herzberg, A. Mistry TASCA SINP Kolkata (IND) S. Lahiri, M. Maiti JAEA Tokai (J) M. Asai, M. Schädel April 14: Univ. Oslo (N) J.P. Omtvedt, A. Semchenkov Begin Search for U Jyväskylä J. Uusitalo Element 119 PSI / Univ. Berne (CH) A. Türler, P. Steinegger U Bogota L.G. Sarmiento ITE Warsaw (PL) M. Wegrzecki Ch.E. Düllmann – DPG Frühjahrstagung 2012 – Johannes Gutenberg-Universität Mainz – 19.-23. März 2012 (How) can we produce weighable quanNNes •For potenNal usefulness: T 1/2 ≥ 100 a "Short term" soluon 1? 15 •QuanNty: > Short(?) term parJal µg (10 atoms) soluon: e.g., 251Cf? Is the most interesng physics on a "strategic" meline done by adding neutrons (not protons)? Narrow pathway to the island of stability just by fusion reactions ! V. Zagrebaev Signature in FPD: EVR-α... (unobserved ....EC-EC-EC... ) ...SHE exists for 1200 a, but nobody knows!! Need 1: detecJon system for EC 21 Need 2: non-destrucJve 1 atom detecJon / manipulaon method! 21 (How) can we produce weighable quanNNes •For potenNal usefulness: T 1/2 ≥ 100 a •QuanNty: > "Short term" soluon?µg (1015 atoms) Fusion reacJons: Next-next(-next...) generaon RIB factories? To put this into historical perspecNve: Is the most interesng Transfer reacons: physics on a "strategic" IRiS? 1950: meline done by adding Nuclear Chemistry Discovery of Cf (Z=98) based on 5'000 neutrons (not protons)? atoms Neutron capture: Next-next(-next...) generaon pulsed reactors? Unl 2012: Search in Nature (Cosmic rays) 8 g (1022 atoms) produced → Factor 1018 W. Loveland Cold fusion New elements from RIB facilities (LOL) DetecNon • Shortest halflives: – Survival through separator? – Disentangling of fast decays? • Longest halflives: – DetecNon by decay chain not opNmal • IdenNficaon through: – Chemical ID – Mass measurement – X-ray fingerprinNng – cross bombardment – alpha chains L.-L. Andersson Rates? • Factories planned: – Dubna – GSI – Others? ECOS report recommended dedicated faciliNes What do we use the extra beamdose for? -> Push boundaries -> Precision studies Spherical Shells • Where is the island of stability? – Where is the shoreline? – Where is the peak? • Experimental body of data sNll very neutron deficient alpha decay spontaneous fission 120 spherical ▼ ▼ Z=117 ▼ ▼ Oganessian 2011 Yu.