  We propose an imaging technique to follow core-hole wave-packet oscillations
in the nitrogen molecule. In this scheme, an attosecond x-ray pulse
core-ionizes the nitrogen molecule and a subsequent attosecond x-ray pulse
probes the evolution of the electron dynamics. We can image the oscillation of
the core-hole between the two atomic sites by measuring the angular correlation
between photoelectrons. Analytical relations for the angular correlation are
derived based on the plane-wave approximation for the photoelectron wave
function. We validate these results with a scattering calculation for the
photoelectron wave function. The feasibility of the experimental realization of
this scheme is discussed in light of current and future capabilities of x-ray
free-electron lasers.
