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We study the bound wave packet launched by an ionizing 30-fs, 800-nm pulse in the ground state of by using a lower intensity pulse to dissociate the ion. The momentum distribution of ions is measured using a velocity map imaging spectrometer. A long delay scan provides enough resolution in the rotational quantum beat spectrum that we can unambiguously separate contributions from vibrational levels between to. By filtering the momentum spectra in the Fourier domain, we reconstruct momentum distributions from either a single vibrational state, or even from a single rotational coherence. These spectra provide us the opportunity to investigate the passage of coherently-prepared ions through light-induced conical intersections between light-dressed and states.