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Summary decay properties of the isotopes of odd-Z elements observed among the products of 48 Ca beam and 237 Np, 243 Am and 249 Bk target reactions. The numbers of the decay chains of the given isotopes, the products of corresponding xn-evaporation channels, observed in experiments with use of the DGFRS [26, 27, 34, 36, 66-70] (in red), chemical setup (in blue) [26, 71, 72] and TASCA (in grey) [73, 74] are shown. The average energies or energy intervals of α particles and half-lives are given for all α emitters observed in these experiments (yellow squares). The energy uncertainties given in brackets correspond to the data with the best energy resolution. For spontaneously fissioning nuclei marked by green squares the half-lives are listed. 

Summary decay properties of the isotopes of odd-Z elements observed among the products of 48 Ca beam and 237 Np, 243 Am and 249 Bk target reactions. The numbers of the decay chains of the given isotopes, the products of corresponding xn-evaporation channels, observed in experiments with use of the DGFRS [26, 27, 34, 36, 66-70] (in red), chemical setup (in blue) [26, 71, 72] and TASCA (in grey) [73, 74] are shown. The average energies or energy intervals of α particles and half-lives are given for all α emitters observed in these experiments (yellow squares). The energy uncertainties given in brackets correspond to the data with the best energy resolution. For spontaneously fissioning nuclei marked by green squares the half-lives are listed. 

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Article
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A review of the discovery and investigation of the 'island of stability' of super-heavy nuclei at the separator DGFRS (FLNR, JINR) in the fusion reactions of (48)Ca projectiles with target nuclei (238)U-(249)Cf is presented. The synthesis of the heaviest nuclei, their decay properties, and methods of identification are discussed. The role of shell...

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Context 1
... first decay chain was observed at the DGFRS on 24 July, 2003. This involved two new elements at once, 288 115 and 284 113, followed by α decays of three new neutron-rich isotopes of the known ele- ments 280 Rg, 276 Mt and 272 Bh and SF of 268 Db (see figure 8). The electron-capture (EC) of 268 Db leading to presumably rapid SF of 268 Rf (T SF ~ 1 s [7]) could not be excluded as well. ...
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... spontaneously fissioning nuclei marked by green squares the half-lives are listed. figure 8). The decay properties of SHN will be discussed in the following section but here we emphasize that the decay properties of nuclei observed in the 243 Am + 48 Ca reaction evidently differ from those produced in the reactions with even-Z target nuclei. ...
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... cross-section values are not given in [73]. The summary decay properties of 287,288 115 are shown in figure 8. ...
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... this new long decay time just could confirm the assump- tion of [66]. In figure 8 we present result of a two-exponential fit [76] of all the available data for 276 Mt which suggests two half-lives. However, more statistics is still needed for definite conclusion. ...
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... of isotopes of the new element 117 was made similarly to that of the isotopes with Z = 115 produced in the 243 Am( 48 Ca, 2-4n) 287 294,293 117 reaction should have lower α-particle energies and respectively, longer lifetimes compared with the isotopes 288 115 and 287 115 produced in the reaction with 243 Am. Indeed, α-decay energies of all the descendant nuclei 289 figure 8). Furthermore, in spite of complex α-particle spectra of odd-Z nuclei, decay properties of 289 115 and 288 115 and descendant nuclei are different (compare T α values for nuclei in figure 8 and shape of α-particle spectra in figure 12 below, especially for isotopes of element 113). ...
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... α-decay energies of all the descendant nuclei 289 figure 8). Furthermore, in spite of complex α-particle spectra of odd-Z nuclei, decay properties of 289 115 and 288 115 and descendant nuclei are different (compare T α values for nuclei in figure 8 and shape of α-particle spectra in figure 12 below, especially for isotopes of element 113). At the same time, α- particle energies, decay times and decay modes of isotopes 289 115, 285 113, and 281 Rg observed in the reactions with 243 Am and 249 Bk agree. ...
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... the partial T α value for 268 Db exceeding that for 270 Db, suggested in [74], by more than two orders of magnitude (≥300 h) seems to be very unlikely. That is why we do not include results for 270 Db in figure 8 and below until finishing detailed analysis of the data ( [36] in [74]). ...
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... α-decay chains of four parent nuclei end by SF of isotopes 266,267,268,270 Db. Only odd-even 281 Rg undergoes SF with small branch for α decay (b α = 12 − + 7 9 %) which is followed by SF of 277 Mt (see figure 8). ...

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... The study on the superheavy elements (SHEs) is one of the most important topics in nuclear physics nowadays [1][2][3][4]. The cross section of fusion-evaporation reactions for producing superheavy nuclei (SHN) is extremely small, in the order of 10 −36 cm 2 and strongly dependent on the combination of two colliding nuclei and the incident energy. ...
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... The production and spectroscopic study of superheavy nuclei (SHN) is currently one of the important topics in nuclear physics. The experiments on the synthesis of SHN with charge numbers Z = 112-118 [1][2][3][4][5][6][7][8][9][10][11] reveal the existence of island of stability for heaviest nuclei. Although the present experimental data do not allow us to fix the center and boarders of this island, they provide some clues for the theory to predict what the island of stability looks like: whether it is of a shape resembling a volcanic island of a well-centered distribution of stable SHN, or forming a coral reef with stable SHN distributed over an archipelago of binding energy peaks. ...
... For example, for the 48 Ca + 232 Th → 277 Ds +3n reaction, we predict a maximum cross section σ 3n ≈ 0.1 pb, which is smaller than the experimental production cross sections σ 4n = 16 +13 −7 pb (E * CN = 40.6 MeV [15]) [33] in the 48 Ca + 226 Ra → 270 Hs +4n reaction and σ 3n ≈ 3, 10, 3 pb in the reactions 48 Ca + 238 U → 283 Cn +3n, 48 Ca + 242,244 Pu → 287,289 Fl +3n, 48 Ca + 245,248 Cm → 290,293 Lv +3n, respectively [1][2][3]. The nucleus with Z = 110 seems to be the boundary nucleus between the mainland (where the last nucleus is Hs) and the island (archipelago) of stability of superheavy nuclei. ...
... The black triangles at the energy axis indicate the excitation energy E * CN of the CN at bombarding energy corresponding to the Coulomb barrier for the sphere-side orientation. The blue diamonds, green squares, red circles, and gray pentagons represent the experimental data[3] with error bars for 2n-, 3n-, 4n-, and 5n-evaporation channels, respectively. The symbols with the arrow indicate the upper limits of evaporation residue cross sections. ...
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