and $a=1.6\xi$ (dashdot line).](Orbit.eps){width="1.0\linewidth"}

The dotted lines show the orbits for $a=0$, i.e., for a doubly quantized vortex. The splitting of the quasiclassical orbits grows with the decrease in the size of the vortex molecule both for the two-vortex and vortex-antivortex configurations. When the intervortex distance is of the order $\xi$ the energy splitting becomes so large ($\delta\varepsilon\sim\Delta_0$) that the simplified equations (\[orbit1\]),(\[orbit2\]) are no longer valid and the spectrum is disturbed in the whole angular domain $0<\theta_p<2\pi$. One can clearly observe that with the decrease in the intervortex distance the CdGM orbits $b=\pm (a/2)\sin\theta_p$ corresponding to zero energy in isolated vortices transform into two lines $\mu=\pm\mu_0$ which correspond to the spectrum of a doubly quantized vortex. Comparing the isoenergetic lines with the unperturbed CdGM ones one can see that the zero energy quasiclassical trajectories do not pass through the vortex center. It means that the LDOS peaks are necessary shifted from the vortex centers as the intervortex distance becomes small enough. This phenomenon can be understood considering the following qualitative arguments. Indeed, when the intervortex distance is large $a\gg\xi$ the equilibrium size of the vortex pair is determined by the stability condition yielding the zero value of Lorentz force 