Excitation of lowest O+-states in two-neutron transfer reactions in even actinides

The spectroscopic factor is considered for two-nucleon transfer reactions involving the excitation of quadrupole one-phonon states. The particle number conservation condition for the collective phonon state is chosen in the form of the adiabatic theories with the moving frame. The variation of the energy gap in the collective phonon state is taken into account as well as the difference of the mean numbers of particles in the initial and final nuclei. Numerical calculations of the spectroscopic factor are carried out for (the p,t)- and (t,p)-reactions for a number of actinide nuclei. (orig.)