LAUSR

Within the framework of dinuclear system model, the synthesis of the superheavy elements (SHEs) $Z=119$ and $Z=120$ is investigated. The entrance channel effects on capture cross section, fusion probability, survival probability, and evaporation residue cross section are investigated. We calculate the production cross sections in 276 possible reactions (with stable projectiles of $Z=20$--30 and targets with the half-lives longer than 20 days) and show the promising ones for the synthesizing SHEs $Z=119$ and $Z=120$. It is found that the systems $^{44}\mathrm{Ca}\phantom{\rule{0.16em}{0ex}}+\phantom{\rule{0.16em}{0ex}}^{252}\mathrm{Es}$ and $^{40}\mathrm{Ca}\phantom{\rule{0.16em}{0ex}}+\phantom{\rule{0.16em}{0ex}}^{257}\mathrm{Fm}$ are the most favorable to produce the SHEs $Z=119$ and $Z=120$ with maximal production cross sections (optimal incident energies) of 4.32 pb (204.27 MeV) and 1.24 pb (205.66 MeV), respectively.