Production mechanism of neutron-deficient actinide isotopes in complete fusion reactions and multinucleon transfer reactions

Abstract

Within the dinuclear system model, unknown neutron-deficient isotopes Np, Pu, Am, Cm, Bk, Cf, Es, Fm are investigated in ${}^{40}$Ca, ${}^{36,40}$Ar, ${}^{32}$S, ${}^{28}$Si,${}^{24}$Mg induced fusion-evaporation reactions and multinucleon transfer reactions with radioactive beams ${}^{59}$Cu,${}^{69}$As,${}^{90}$Nb,${}^{91}$Tc, ${}^{94}$Rh, ${}^{105,110}$Sn, ${}^{118}$Xe induced with ${}^{238}$U near Coulomb barrier energies. The production cross sections of compound nuclei in the fusion-evaporation reactions and fragments yields in the multinucleon transfer reactions are calculated within the model. A statistical approach is used to evaluate the survival probability of excited nuclei via the both reaction mechanisms. A dynamical deformation is implemented into the model in the dissipation process. It is found that charge particle channels (alpha and proton) dominate in the decay process of proton-rich nuclides and the fusion-evaporation reactions are favorable to produce the new neutron-deficient actinide isotopes. The total kinetic energies and angular spectra of primary fragments are strongly dependent on colliding orientations.

Comments: 14 pages, 9 figures, 3 tables