Entrance channel mass asymmetry dependence of compound nucleus formation

The fusion reactions 48Ca + 154Sm and 16O + 186W leading to the same compound nucleus 202Pb are studied within the framework of an improved isospin dependent quantum molecular dynamics model. The entrance channel mass asymmetry dependence of compound nucleus formation is found by analyzing the shell correction energies, Coulomb barriers and fusion cross sections. The calculated fusion cross sections agree quantitatively with the experimental data. We conclude that the compound nucleus formation is favorable for the system with larger mass asymmetry.