Stability of superheavy nuclei against α-decay and spontaneous fission

2013 ◽  
Vol 898 ◽  
pp. 24-31 ◽  
Author(s):  
Chang Xu ◽  
Xin Zhang ◽  
Zhongzhou Ren
2007 ◽  
Vol 16 (04) ◽  
pp. 949-956 ◽  
Author(s):  
YURI OGANESSIAN

The formation and decay properties of the heaviest nuclei with Z = 112 - 116 and 118 were studied in the reactions 238 U , 242,244 Pu , 243 Am , 245,248 Cm and 249 Cf +48 Ca . The new nuclides mainly undergo sequential α-decay, which ends with spontaneous fission. The total time of decays ranges from 0.5 ms to about 1 day, depending on the proton and neutron numbers in the synthesized nuclei. The atomic number of the new elements 115 and 113 was confirmed also by an independent radiochemical experiment based on the identification of the neutron-rich isotope 268 Db (TSF ≈ 30 h ), the final product in the chain of α-decays of the odd–odd parent nucleus 288115. The comparison of the decay properties of 29 new nuclides with Z = 104 - 118 and N = 162 - 177 gives evidence for the decisive influence of the structure of superheavy nuclei on their stability with respect to different modes of radioactive decay. The investigations connected with the search for superheavy elements in Nature (cosmic rays) and prospects of superheavy element research are also presented.


2005 ◽  
Vol 14 (03) ◽  
pp. 365-372 ◽  
Author(s):  
A. BARAN ◽  
M. KOWAL ◽  
Z. ŁOJEWSKI ◽  
K. SIEJA

In the framework of various macroscopic-microscopic models we examine the ground state properties: separation energies, mean square charge radii, electric quadrupole moments as well as fission barriers, mass parameters, spontaneous fission and α decay half-lives of superheavy nuclei. Four macroscopic models and two models of pairing interactions are applied and studied. The approach is based on the deformed Woods-Saxon potential. Spontaneous fission half-lives are calculated within a multi-dimensional dynamical-programming method where the action integral is minimized within the three dimensional space of the nuclear deformation parameters {β2, β4, β6}.


2020 ◽  
Vol 29 (05) ◽  
pp. 2050025
Author(s):  
S. A. Seyyedi

In this study, we have investigated the [Formula: see text]-decay chains of even–even superheavy nuclei [Formula: see text] in the range of [Formula: see text]. The Hartree–Fock–Bogoliubov model is used to calculate the binding energy of these superheavy nuclei. We have included the so-called SkP skyrme function as an effective force and the quadruple deformations. The semi-empirical formulas are used in the reproducing [Formula: see text]-decay and spontaneous fission half-lives of these superheavy nuclei. By studying the decay chains of the Z = 120 isotopes and comparing them with the half-lives of spontaneous fission, it is predicted that the elements [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text],[Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text] are more stable than the neighboring isotopes in their parent [Formula: see text]-decay chain. The corresponding neutron and proton numbers represent magical behavior that is in agreement with the numbers predicted before. In this range, the predicted nuclei are found to have large enough half-lives to synthesize them in a laboratory.


1971 ◽  
Vol 26 (4) ◽  
pp. 643-652 ◽  
Author(s):  
Jens Grumann ◽  
Tihomir Morovic ◽  
Walter Greiner

AbstractThe potential energy surface has been calculated by two methods which are compared with re­spect to spontaneous fission. In the first one essentially the sum of the single particle energies is computed as was done in a previous paper3 while in the second one the Strutinsky technique of renormalizing to a liquid drop model has been applied. Also the half-lives for electron capture are investigated together with the predictions of the half-lives for spontaneous fission and α-decay. The results support the existence of superheavy nuclei in the regions around Z = 114 and Z = 164.


2021 ◽  
pp. 122250
Author(s):  
Haitao Yang ◽  
Zhongxia Zhao ◽  
Xiaopan Li ◽  
Yan Cai ◽  
Xiaojun Bao
Keyword(s):  

2006 ◽  
Vol 15 (07) ◽  
pp. 1587-1599 ◽  
Author(s):  
ZHONGZHOU REN ◽  
DINGHAN CHEN ◽  
CHANG XU

Superheavy elements have provided a good test of the validity of both nuclear structure models and nuclear decay models in a large mass region. We firstly review the recent progress on theoretical studies of superheavy nuclei. Emphasis is placed on the structure and decay of superheavy nuclei. Then theoretical results of odd-odd nuclei with Z = 109 - 115 are presented and discussed. It is clearly demonstrated that there is shape coexistence for the ground state of many superheavy nuclei from different models and many superheavy nuclei are deformed. In some cases superdeformation can become the ground state of superheavy nuclei and it is important for future studies of superheavy nuclei. This can lead to the existence of low-energy isomers in the superheavy region and it plays an important role for the stability of superheavy nuclei. As α-decay and spontaneous fission plays a crucial role for identifications of new elements, we also review some typical models of α-decay half-lives and spontaneous fissions half-lives. Some new views on superheavy nuclei are presented.


2018 ◽  
Vol 193 ◽  
pp. 04001
Author(s):  
G. Bélier ◽  
J. Aupiais ◽  
G. Sibbens ◽  
A. Moens ◽  
D. Vanleeuw

A novel detector has been used, in order to perform measurements of spontaneous fission to α-decay ratios for 240Pu, 242Pu and 252Cf isotopes. The detectors are based on the well-known technique of liquid scintillating counting. The principle and advantages of the use of such detectors in nuclear physics is discussed. The application to the characterization of spontaneous fission is described and it is demonstrated that highly precise measurements are possible, and that the main limit is due to the isotopic content knowledge of the measured samples.


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