Study of alpha decay chains of superheavy nuclei and magic number beyond Z = 82 and N = 126

We study various α-decay chains on the basis of the preformed cluster decay model. Our work targets the superheavy elements, which are expected to show extra stability at shell closure. Our computations identify the following combinations of proton and neutron numbers as the most stable nuclei: Z=112, N=161,163; Z=114, N=171,178,179; and Z=124, N=194. We also investigate the alternative of heavy cluster emissions in the decay chain of ³⁰¹120, instead of α decay. Our study of cluster radioactivity shows that the half-life for ¹⁰Be decay in ²⁸⁹114 is larger, indicating enhanced stability at Z=114, N=175. Similar calculations concerning the emission of ¹⁴C and ³⁴Si from ³⁰¹120 find the more stable combinations Z=114, N=173, and Z=106, N=161, respectively. From the same parent, ³⁰¹120, the emission of a ⁴⁹⁻⁵¹Ca cluster yielding a Z=100, N=152 daughter is the most probable. (author)