No abstract

The improved Kelson-Garvey (ImKG) mass relations are proposed from the mass differences of mirror nuclei. The masses of 31 measured proton-rich nuclei with 7 ≤ A ≤ 41 and −5 ≤ (N − Z) ≤ −3 can be remarkably well reproduced by using the proposed relations, with a root-mean-square deviation of 0.398 MeV, which is much smaller than the results of and Isobar-Mirror mass relations (0.647 MeV). This is because many more masses of participating nuclei are involved in the ImKG mass relations for predicting the masses of unknown proton-rich nuclei. The masses for 144 unknown proton-rich nuclei with 6 ≤ A ≤ 74 are predicted by using the ImKG mass relations. The one-and two-proton separation energies for these proton-rich nuclei and the diproton emission are investigated simultaneously. * Electronic address: tianjunlong@gmail.com

The fusion probability in "hot" fusion reactions leading to the synthesis of super-heavy nuclei is investigated systematically. The quasi-fission barrier influences the formation of the super-heavy nucleus around the "island of stability" in addition to the shell correction. Based on the quasifission barrier height obtained with the Skyrme energy-density functional, we propose an analytical expression for the description of the fusion probability, with which the measured evaporation residual cross sections can be reproduced acceptably well. Simultaneously, some special fusion reactions for synthesizing new elements 119 and 120 are studied. The predicted evaporation residual cross sections for 50 Ti+ 249 Bk are ∼ 10 − 150 fb at energies around the entrance-channel Coulomb barrier. For the fusion reactions synthesizing element 120 with projectiles 54 Cr and 58 Fe, the cross sections fall to a few femtobarns which seems beyond the limit of the available facilities.

The nuclear symmetry energy coefficients of finite nuclei are extracted by using the differences between the masses of isobaric nuclei. Based on the masses of more than 2400 nuclei with A = 9 − 270, we investigate the model dependence in the extraction of symmetry energy coefficient. We find that the extraction of the symmetry energy coefficients is strongly correlated with the forms of the Coulomb energy and the mass dependence of the symmetry energy coefficient adopted. The values of the extracted symmetry energy coefficients increase by about 2 MeV for heavy nuclei when the Coulomb correction term is involved. We obtain the bulk symmetry energy coefficient S 0 = 28.26 ± 1.3 MeV and the surface-to-volume ratio κ = 1.26 ± 0.25 MeV if assuming the mass dependence of symmetry energy coefficient a sym (A) = S 0 (1 − κ/A 1/3 ), and S 0 = 32.80 ± 1.7 MeV, κ = 2.82 ± 0.57 MeV when a sym (A) = S 0 (1 + κ/A 1/3 ) −1 is adopted.

To investigate the influence of nuclear finite-size effects on the fragmentation in heavy-ion colli-