Structure effects in the region of superheavy elements via the  -decay chain of²⁹³118

Abstract

The α-decay chain of 293 118, first proposed in the Berkeley cold fusion experiment 208 Pb( 86 Kr,1n) and now retracted, is calculated by using the preformed cluster model (PCM) of one of us (RKG). Also, the possible branchings of α-particles to heavier cluster decays of all the parents in this chain are calculated for the first time. The calculated Q-values, penetrabilities and preformation factors for α-decays suggest that the 285 114 nucleus with Z=114, N=171 is a magic nucleus, either due to the magicity of Z=114, or of N=172 or of both. The N=172 is proposed to be a magic number in certain relativistic mean-field calculations, but with Z=120. The calculated cluster decays point to new interesting possibilities of 14 C decay of the 281 112 parent, giving rise to a (reasonably) deformed Z=106, N=161, 267 106 daughter (N=162 being now established as the deformed magic shell) or to a doubly magic 48 Ca cluster emitted from any of the parent nucleus in the α-decay chain. Apparently, these are exciting new directions for future experiments.

Neutron and proton shell closure in the superheavy region via cluster radioactivity in 280–314116 isotopes

“…All these decay show the role of spherical shell closure of daughter at N = 184. 8 Be cluster from 302 116, 10 Be and 12 C from 304 116, 8 Be, 10 Be, 12 C and 14 C from 306 116, 10 Be, 12,16 C from 308 116, 14 C, 16 C and 20 O from 310 116 and We would like to point out that Gupta et al [47] studied the shell structure in superheavy region by calculating Q-values, barrier penetrability and preformation probability for both alpha and heavy cluster decay. These authors studied alpha decay of 293 118 and its subsequent parents ending the chain in 269 106, and cluster decays of all these parents in the alpha decay chain.…”

“…The calculation done by these authors for various cluster decays from these parents (plot of log 10 T 1/2 and Q-value vs. mass number of parent, figure 4 of ref. [47]) also indicate the presence of deformed shell closure at N = 162 and Z = 106.…”

“…This is supported by a small Q-value and small (deeper minima) penetrability and preformation factor (figure 3 of ref. [47]). The calculation done by these authors for various cluster decays from these parents (plot of log 10 T 1/2 and Q-value vs. mass number of parent, figure 4 of ref.…”

Heavy particle radioactivity from superheavy nuclei leading to 298114 daughter nuclei

“…Theoretical predictions on the shell closures at Z = 114, 120, 126 and N = 162, 172, 184 in the super-heavy mass region have been done by many authors [36][37][38]. Within the preformed cluster model, Gupta et al, [38] have calculated the alpha half-life time value of 285 114, indicating that the isotope is stable against α decay and the magicity of protons at Z = 114 or of neutrons at N ≈ 172 was accounted for this stability.…”

αdecay chains study for the recently observed superheavy elementZ=117within the isospin cluster model

“…The Isospin Cluster Model (ICM) calculations for the 293,294 117 alpha decay chains are compared with the experimental results [9], the macroscopic-micrscopic(MM) [10], RMF based (using NL3 and SFU Gold forces parameters) [11,12] model calculations. In our earlier work for the α-decay chains calculation [13][14][15], preformed cluster model [16] was used and it has been observed that calculated results could be improved using the isospin physics in the model. So, the earlier used model is modified with the same idea and hence obtained very nice results from the present ICM calculations.…”