Unexpected Strong Decay Mode of Superheavy Nuclei

Abstract

Calculations of half-lives of superheavy nuclei (SH) show an unexpected result: for some of them heavy particle radioactivity (HPR) dominates over alpha decay—the main decay mode of the majority of recently discovered SHs. The result is important for theory and future experiments producing heavier SHs with a substantial amount of funding. The standard identification technique by alpha decay chains will be impossible for these cases. HPR had been predicted in 1980 four years before the first experiment. The daughter is mainly the doubly magic \(^{208}\)Pb. We changed the concept of HPR to allow emitted particles with \(Z_e > 28\) from parents with \(Z > 110\) (daughter around \(^{208}\)Pb). We find a trend toward shorter half-lives and larger branching ratios relative to alpha decay for heavier SHs. A new table of measured masses AME11 and the theoretical LiMaZe01, KTUY05 and FRDM95 tables are used to determine Q-values.