Superheavy particles of masses ' 1013 − 1014 GeV with lifetimes ' 1010 − 1022 years are very interesting, since their decays may account for the ultra-high energy (UHE) cosmic rays discovered beyond the Greisen-Zatsepin-Kuzmin cutoff energy E ∼ 5 × 1010 GeV. We show that the presence of such long-lived superheavy particles is a generic prediction of QCD-like SU(Nc) gauge theories with Nf flavor...

The dark matter in the universe can be in the form of a superheavy matter species (wimpzilla). Several mechanisms have been proposed for the production of wimpzilla particles during or immediately following the inflationary epoch. Perhaps the most attractive mechanism is through gravitational particle production, where particles are produced simply as a result of the expansion of the universe. ...

Fifteen correlated α-decay chains starting from the odd-A superheavy nucleus Fl289 were observed following fusion-evaporation reaction Ca48+Pu244. The results call for at least two parallel sequences different states of Fl289. This implies that close-lying levels in nuclei along these have quite spin-parity assignments. Further, α-electron and α-photon coincidences, as well fine structure decay...