Structure of superheavy elements suggested in title reaction of Kr-86 WithPb-208 - art. no. 064319

The structure of superheavy elements claimed to have been discovered in the recent Pb-208(Kr-86,n) reaction at Berkeley is systematically studied in t he relativistic mean held (RMF) approach. It is shown that various usually employed RMF forces, which give a fair description of normal stable nuclei, give different predictions for superheavy elements. Among the effective fo rces we tested, TM1 seems to be the best candidate to describe superheavy e lements. The binding energies of the (293)118 nucleus and its alpha-decay d aughter nuclei obtained using TM1 agree with those of FRDM within 2 MeV. A similar conclusion, that TM1 is the best interaction, is also drawn from th e calculated binding energies for Pb isotopes with the relativistic continu um Hartree-Bogoliubov (RCHB) theory. Using the pairing gaps obtained from t he RCHB and taking into account the blocking effect for neutrons, RMF calcu lations with deformation are carried out for the structure of superheavy el ements. The binding energy, shape, single particle levels, and the Q values of the alpha-decay Q(alpha) are discussed, and it is shown that the pairin g correlation, blocking effect, and deformation art essential to properly u nderstand the structure of superheavy elements. The Q(alpha) values are cal culated for the ground-state-to-ground-state transitions and for those resp ecting the angular momentum selection rule, and are compared with data.