Workshop on The Future of Superheavy Element Research February , 2004 Gesellschaft f ü r Schwerionenforschung Darmstadt, Germany

Ds Mt Hs Bh Sg Db Rf Lr No Md Es Cf Fm One End of Nuclear Chart  SF  + or EC - Pb + 64 Ni → 271 Ds + n 209 Bi + 64 Ni → n 209 Bi + 70 Zn →

RILAC Facility 18GHz ECR Ion Source RFQ-Linac CSM Acc. Tanks RILAC Acc. Tanks GARIS CSM Dec. Tank

RIKEN

MCP1 MCP2 SSD box PSD ions Focal Plane Detectors

New Rotating Target  = 300 mm,  = 2000 rpm cf. old one  = 125 mm,  = 1000 rpm Tested with 1p  A 86 Kr beam

(v/v 0 )Z 1/3 q eq Bohr’s theorem 208 Pb 209 Bi 169 Tm 208 Pb 209 Bi 198 At 192 Bi 265 Hs 209 Bi 208 Pb 212 Ac 234 Bk 245 Fm 255 Lr 254 No 204 Fr 203 Fr v0: Bohr velocity

system E  BB E  BB E  BB MeV TmMeV TmMeV Tm 208 Pb + 58 Fe Pb + 64 Ni Pb + 70 Zn projectile target recoil compound nucleus Ep/EcnEr/Ecn  p/  cn  r/  cnB  p/B  cnB  r/B  cn energy separator velocity separator gas-filled separator

Hs 263 Sg 259 Rf 255 No 251 Fm 255 Md 11 22 33 44 55 208 Pb + 64 Ni → 271 Ds + n

11 22 33 44 5 E  (MeV) Counts/100keV 11 22 33 44 55 Tdecay Counts/bin s 10s0.1s1ms s 10s0.1s1ms 1000s 10s0.1s1ms 1000s 10s0.1s1ms 1000s 10s0.1s1ms  s ab  =2.9ms  =120ms  =77ms  =1.0s  =3.7s  =220s

NucleinRIKENnGSIT 1/ msimproved 271m msconfirmed 267 Hs msimproved 267m Hs spossible Eopt( 64 Ni)=314MeV Eopt(cm)=240MeV Summary of 208 Pb + 64 Ni → n reaction

Mt 264 Bh 260 Db 256 Lr 252 Md 256 No  1 (14)  2 (14)  3 (12)  4 (11) 55 55 SF (2) SF (1) 209 Bi + 64 Ni → n

Mt 264 Bh 260 Db 256 Lr 252 Md 256 No  1 (14)  2 (14)  3 (12)  4 (11) 55 55 260 Rf 264 Sg SF (2) SF (1) possibility not excluded experimentally 209 Bi + 64 Ni → n

11 22 33 44 55 11 22 33 44 5 s100s1s10ms 100  s Tdecay 254 Md ← 256 Lr ← 260 Db ← 264 Bh ← 268 Mt ←  =5.5ms  =30ms  =1.3s  =8.2s  =26s

RIKENGSI Nuclei n T 1/2 EE E fiss. n T 1/2 E  MeV ms10.2~ ms10.8~ Mt ms9.4~ ms10.1~ Bh s8.86~ s9.1~ Db s8.35~ s9.1~ Lr s8.35~ s8.4~8.5 Eopt( 64 Ni)=319MeV Eopt(cm)=244MeV Summary of 209 Bi + 64 Ni → n reaction

period9/5/2003 ～ 12/29/2003 Beam Energy5.03 AMeV 348 MeV at target half depth Total Dose1.21x10 19 Target Thickness1.37x10 18 /cm 2 (0.48 mg/cm 2 )  _GARIS0.8(assumption)  (1-ev.)7.5x cm 2 upper limit (1  )1.38x cm 2 Irradiation time1390 Hours(58 Days / 74 Days) Beam Intensity2.42x10 12 /s(0.4 p-  A) Summary of 209 Bi + 70 Zn experiment

Atomic Number 1b1b 1nb 10nb 100nb 100pb 10pb 1pb 0.1pb 208 Pb, 209 Bi(HI,1n) reaction present work

Z Ecm （ MeV) Ex (MeV) KUTYMøllerMy & Sw

Z Ecm （ MeV) Ex (MeV) Ecm – E 2nd_fission （ MeV) KUTYMøllerMy & SwKUTYMøllerMy & Sw

K. MorimotoRIKEN D. KajiCNS H. HabaRIKEN E. IdeguchiRIKEN R. KanumgoRIKEN K. KatoriRIKEN H. KouraRIKEN T. OhnishiRIKEN A. OzawaRIKEN T. SudaRIKEN I. TanihataRIKEN A. YonedaRIKEN A. YoshidaRIKEN H. KudoNiigata U. K. SuekiUniv. of Tsukuba F. Tokanai Yamagata U. H. XuIMP Lanzhou Y.-L. ZhaoIHEP Beijing T. ZengPeking U. A. V. YereminFLNR JINR J. PeterCaen/GANIL

February 17, 2004 FEST COLLOQUIUM ： On the Occasion of Sigurd Hofmann’s 60th Birthday What Do We Know about SHE - Expectations and RealityYuri Oganessian February 18, 2004 Chair:Gottfried Münzenberg Welcome Walter Henning Theory of Superheavy Nuclei: Old and New - Open ProblemsWalter Greiner Chemistry of Spherical Superheavy Elements - The Road to SuccessHeinz Gäggeler Superheavy Element Research at Berkeley Ken Gregorich Possibilities of the RF Nuclear Center Arzamas-16´ in Producing Pure Actinide Isotopes for Science and Applications Stanislav Vesnovskii In Beam Studies of SHE at High Beam Intensities Matti Leino Superheavy-Element Experiments at RIKEN Kosuke Morita Studies of SHE at GANILChristelle Stodel Heavy Element Research at IMP LanzhouWenlong Zhan Heavy Element Research with Laser Spectroscopy and Buffer Gas Traps Hartmut Backe Efficient Production of Intensive Beams of Rare Isotopes Georgy Gulbekian Steps towards an Optimized Linac for SHE Production at GSI Ulrich Ratzinger Studies of SHE at High Beam Intensities Sigurd Hofmann Closing Remarks Walter Henning

GSI SHIP

JINR/FLNR DUBNA Gas-Filled Separator

JINR/FLNR DUBNA

LBNL BGS

GANIL LISE (Wien Filter)

Z=110 に対する計算値

(v/v 0 )Z 1/3 q eq 2004 年 1 月 9 日於京都大学理学部物理学第二教室

Pb Bi Po At Rn Fr Ra Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr Rf Db Sg Bh Hs Mt Tm( 40 Ar,5n) 204 Fr 169 Tm( 40 Ar,6n) 203 Fr 169 Tm( 48 Ca,5n) 212 Ac 208 Pb( 40 Ar,3n) 245 Fm 208 Pb( 48 Ca,2n) 254 No 209 Bi( 48 Ca,2n) 255 Lr 140 Ce (58 Fe,p5n) 192 Bi 140 Ce( 64 Ni,p5n) 198 At 208 Pb( 58 Fe,n) 265 Hs 208 Pb( 64 Ni,n) Bi( 64 Ni,n)

v/v 0 Transmission

Experimental conditions Beam 64 Ni0.4 ～ 1 p  A Total dose4.0 x Target 208 Pb190 ～ 250  g/cm 2 (98% enriched) evaporated on 30  g/cm 2 C covered by 10  g/cm 2 C B  (GARIS)2.05 Tm P (GARIS)75Pa Counting rate10 ～ 20cps

Summary of the measurement in year Pb( 64 Ni,n) reaction datedaysE in Dose (10 18 ) number of events T av (  g/cm 2 )  (pb) < < E in :energy from the accelerator. T av : average target thickness Total 年 1 月 9 日於京都大学理学部物理学第二教室

11 22 33 44 5 E  (MeV) T decay (s)

 (pb) E( 64 Ni) /MeV RIKEN GSI 208 Pb + 64 Ni → n statistical (1  ) errors energy loss in the target

  Hs  Sg  Rf  No Ep TTEETTEETTEETTEETTEE #MeVmsMeVmsMeVmsMeVs s 1Ju b a b a b 2Ju a a b a a 3Ju a a a 4Ju a 5Sp b b a a a 6Sp a b b b a 7Sp b b a b a 8Sp b a b a b 9Sp b b a a 10Sp a a b a 11Sp a b a b b 12Sp b a b a 13No a b a 14No a a b b

Experimental conditions Beam 64 Ni0.7 ～ 1.8 p  A Total dose1.30 x Target 209 Bi210 ～ 310  g/cm 2 evaporated on 30  g/cm 2 C covered by 10  g/cm 2 C B  (GARIS)2.05 Tm P (GARIS)75Pa Counting rate2 ～ 10cps

Summary of the measurement in year Bi( 64 Ni,n) reaction datedaysE in Dose (10 18 ) n T av (  g/cm 2 )  (pb) < E in :energy from the accelerator. T av : average target thickness Total

    CN Mt 256 Lr 260 Db 264 Bh  252 Md 17-Feb ms MeV (PSD) 13.0 ms MeV (PSD) 1.45 s 9.60 MeV (PSD) s 9.05 MeV (PSD) 21.9 s 8.37 MeV (PSD) E proj =323MeV     CN Mt 256 Lr 260 Db 264 Bh  252 Md 17-Feb ms MeV (PSD+SSD) 9.2 ms MeV (PSD) 1.38 s 9.81 MeV (PSD+SSD) 1.93 s 9.17 MeV (PSD+SSD) 11.9 s 8.39 MeV (PSD+SSD) 14.9 ms MeV (PSD+SSD)     CN Mt 256 Lr 260 Db 264 Bh  252 Md 20-Feb ms 1.12 MeV (PSD) escape 21.8 ms 9.85 MeV (PSD) 0.51 s 9.34 MeV (PSD) 33.5 s 8.65 MeV (PSD) 209 Bi( 64 Ni,n) st 2nd 3rd

   CN Mt 260 Db 264 Bh 26-Feb ms MeV (PSD+SSD) ms MeV (PSD) 0.54 s 9.57 MeV (PSD) 1.71 s 231 MeV (PSD+SSD) E proj =323MeV     CN Mt 256 Lr 260 Db 264 Bh 26-Feb ms MeV (PSD) 36.6 ms MeV (PSD+SSD) 1.87 s 9.66 MeV (PSD+SSD) 1.52 s 9.40 MeV (PSD) 2.82 ms MeV (LG)     CN Mt 256 Lr 260 Db 264 Bh 8-Apr ms MeV (PSD+SSD) 0.44 s 9.58 MeV (PSD) s 8.81 MeV (PSD) 209 Bi( 64 Ni,n) S.F. 6th 5th 4th

  CN Mt 264 Bh 15-Apr ms MeV (PSD+SSD) ms 2.76 MeV (PSD)esc 0.97 s 208 MeV (PSD) E proj =323MeV     CN Mt 256 Lr 260 Db 264 Bh  252 Md 14-Apr ms MeV (LG) ms MeV (PSD) 3.6 ms 9.31 MeV (PSD) 4.87 s 9.01 MeV (PSD) s 8.50 MeV (PSD) 5.11 ms MeV (PSD)     CN Mt 256 Lr 260 Db 264 Bh  252 Md 16-Apr ms MeV (PSD) 1.34 s 9.50 MeV (PSD) 3.69 s 9.10 MeV (PSD) 7.87 s 8.41 MeV (PSD) 209 Bi( 64 Ni,n) S.F. 9th 8th 7th

    CN Mt 256 Lr 260 Db 264 Bh 5-May ms MeV (PSD+SSD) 32.4 ms MeV (PSD) 1.91 s 8.87 MeV (PSD+SSD) s MeV (PSD) E proj =320MeV 30-Apr ms MeV (PSD+SSD)     CN Mt 256 Lr 260 Db 264 Bh  252 Md 5-May ms MeV (PSD) 1.0 s 9.85 MeV (PSD) 1.14 s 9.14 MeV (PSD) s 8.47 MeV (PSD+SSD) 209 Bi( 64 Ni,n)   CN Mt 264 Bh 1.0 ms MeV (PSD) 8.8 ms MeV (PSD+SSD) 4.93 s 206 MeV (PSD+SSD) S.F. 12th 11th 10th

    CN Mt 256 Lr 260 Db 264 Bh  252 Md 12-May ms MeV (PSD+SSD) 3.35 ms MeV (PSD) 0.81 s 9.63 MeV (PSD) 2.42s MeV (PSD+SSD) 6.85 s 8.63 MeV (PSD) E proj =323MeV 8-May-2003     CN Mt 256 Lr 260 Db 264 Bh 6.84 ms MeV (PSD+SSD) 37.2 ms 9.40 MeV (PSD) 1.23 s 9.56 MeV (PSD+SSD) 0.33 s 8.29MeV (PSD+SSD) 209 Bi( 64 Ni,n) th 13th

11 22 33 44 5 T decay (s) E  (MeV) 254 Md ← 256 Lr ← 260 Db ← 264 Bh ← 268 Mt ←

* * CN Q-valueExopt.CN Q-valueExopt. MeV KUTY Møller My. & Sw Optimum excitation energies for 1n evaporation channel

213 Fr MeV 4p transfer 211 Po MeV pn transfer 211m Po MeV pn transfer 212 At MeV 2pn transfer 212m At 7.837,7.897 MeV 2pn transfer 213 Rn MeV 3pn transfer 214 Fr MeV 4pn transfer 214m Fr 8.546, MeV 4pn transfer 199 At MeV p4n evap. 196 Po MeV  4n evap. 197 Po MeV  3n evap. 198 Po MeV 199 Po MeV 200 Po MeV 197m Po MeV E  (MeV) Counts/10keV 140 Ce + 64 Ni evaporation residues 209 Bi + 64 Ni transfer products 209 Bi Nat. Ce 64 Ni to GARIS system check & energy calibration RARF_PAC 02Jul2003