Doubly magic nucleus (108)(270)Hs162.
Theoretical calculations predict 270Hs (Z=108, N=162) to be a doubly magic deformed nucleus, decaying mainly by alpha-particle emission. In this work, based on a rapid chemical isolation of Hs isotopes produced in the 26Mg+248Cm reaction, we observed 15 genetically linked nuclear decay chains. Four chains were attributed to the new nuclide 270Hs, which decays by alpha-particle emission with Qalpha=9.02+/-0.03 MeV to 266Sg which undergoes spontaneous fission with a half-life of 444(-148)(+444) ms. A production cross section of about 3 pb was measured for 270Hs. Thus, 270Hs is the first nucleus for which experimental nuclear decay properties have become available for comparison with theoretical predictions of the N=162 shell stability.
Dvorak
J
J
Technische Universität München, D-85748 Garching, Germany.
Brüchle
W
W
Chelnokov
M
M
Dressler
R
R
Düllmann
Ch E
ChE
Eberhardt
K
K
Gorshkov
V
V
Jäger
E
E
Krücken
R
R
Kuznetsov
A
A
Nagame
Y
Y
Nebel
F
F
Novackova
Z
Z
Qin
Z
Z
Schädel
M
M
Schausten
B
B
Schimpf
E
E
Semchenkov
A
A
Thörle
P
P
Türler
A
A
Wegrzecki
M
M
Wierczinski
B
B
Yakushev
A
A
Yeremin
A
A