Effect of proton and neutron transfer on synthesizing superheavy elements in heavy ion reactions

The limitation of the one dimensional master equation with the mass number of project-like fragment as the variable is discussed. A two-dimensional master equation with neutron and proton numbers of the project-like fragment as variables is set up, and solved numerically by means of a two step difference scheme to obtain fusion probability. The new equation is suitable for studying fusion reactions with any projectile-target combination, and can better fit the experimental data, so that it can provide a large probability to choose the reaction system for synthesizing a certain superheavy nucleus. The influence of projectile-target combinations with different isospins on the cross-sections of compound nuclei is studied. (authors)