Gauge angle dependence in TDHFB calculations of ${}^{20}$O + ${}^{20}$O head-on collisions with the Gogny interaction

A numerical method to solve the TDHFB equations by using a hybrid basis of the two-dimensional harmonic oscillator eigenfunctions and one-dimensional Lagrange mesh with the Gogny effective interaction is applied to the head-on collisions of the superfluid nuclei ${}^{20}$Os. Taking the energies around the barrier top energy, the trajectories, pairing energies, and numbers of transferred nucleons are displayed. Their dependence on the relative gauge angle at the initial time is studied by taking typical sample points of the gauge angle. It turned out that the functional form of the flux of the neutrons across a section plane is proportional to the sine of the two times of the gauge angle.