B = av A - as A2/3 - ac Z(Z-1)A-1/3 - asym (A-2Z)2/A ? ap A-3/4

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Bindungsenergie (semi-) empirische Massenformel
von Bethe-Weizsäcker
B av A - as A2/3 - ac
Z(Z-1)A-1/3 - asym (A-2Z)2/A ? ap A-3/4
Volumen Oberfläche Coulomb
Symmetrie Paarung
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History of the synthesis and discovery of super
heavy elements (SHE)
With Fermis method and the 60-cyclotron 7
Transurane could (Z93-98) Be synthesised. By
irradiation of actinides with light ions the
elements up Z106 could be Produced in Berkeley
(CA, U.S.A.) and in Dubna (Rußland).
(P. Armbruster, Spektrum der Wissenschaft,
Dezember 1996)
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The Limits of Stability
Island of stability
?
stabilisation via shelleffects
Z 100
liquid dropmodel
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Synthese von Element 107
Kalte Fusion Erzeugung eines Verbundkerns mit
geringer Anregungsenergie
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Schalenkorrekturen Eshell in der Region der
schweren ElementeP. Möller et al.
at GSI Elements 107-112 first synthesised and
unambiguously identified 107 Bh 108 Hs 109
Mt
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Alpha -Zerfall
klassisch verboten.
Quantenmechanischer Tunneleffekt
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a-Zerfall Halbwertszeit vs. Q-Wert
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a-Zerfall Q-Wert gegen Massenzahl
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Stop- und Backward-Detector Array
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58Fe209Bi ? 267Mt- an Example Chain
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SHE Cross Section Systematic (1n ER Reactions)
first hint for deviation from empirically
observed trend from LBNL?
X
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SHE Cross Section Systematic (xn ER Reactions)
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Time Limits for the Heavy Element Production
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The SHIPTRAP Project
SHIP
Kinematic seperator fusion of A40 to 80
projectiles with Pb, Bi target 0.5 mg/cm2 energy
5 A MeV intens. 2-5 1012 ions/s repetition rate
50 Hz pulse duration 6ms
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The SHIPTRAP Project
Combined In-Flight and ISOL facility for
fusion products
Gas cell
RFQ cooler and buncher
Penning trap
Mass measurements for trans-uranium
elements NZ nuclei
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Synthesis and Identification of SHE at SHIP
277112
kinematic separation in flight
identification by ?-? correlations to known
nuclides