The ground state properties of He isotopes are studied in the nonlinear relativistic mean-field (RMF) theory with force parameters NL-SH and TM2. The modified Glauber model as a gatekeeper is introduced to check the calculations. The investigation sh
ows that the RMF theory provides a good description on the properties of He isotopes. The many-body space information of 4He + neutrons are obtained reliably. As a product, the calculation gives a strong evidence for neutron halo in 5He.
The direct radiative capture process is well described by the spherical potential model. In order for the model to explain direct captures more accurately, the effect of the nuclear deformation has been added and analyzed in this work, since most nuc
leuses are not spherical. The results imply that the nuclear deformation largely affects the direct capture and should be taken into account during discussing direct capture reactions.
The strong coupling Eliashberg theory plus vertex correction is used to calculate maps of transition temperature (Tc) in parameter-space characterizing superconductivity. Based on these Tc maps, crossover behaviors are found when electron-phonon inte
raction increases from weak-coupling region to strong coupling region. Especially, the combined interaction of vertex correction and Coulomb interaction can efficiently depress Tc from extremely high values in standard strong-coupling theory to reasonable values found in experiments and successfully explain the doing-dependent Tc of cuprate superconductors. The strong non-adiabatic effect is the barrier for high-Tc in compounds with compositions of light atoms and with high phonon frequencies.
