Quantitative comparison between theory and experiment for dissociation of H$_{2}^+$ in ultrashort laser pulses*

We have performed calculations for H$_{2}^+$ dissociation in an intense laser pulse including all possible physical processes except ionization. In particular, we have included nuclear vibration and rotation as well as electronic excitation. We compare these results to data we have obtained from kinematically complete measurements, including both the ionic H$^+$ and neutral H fragments dissociated from an H$_{2}^+$ beam, achieved through coincidence three-dimensional momentum imaging. To make the comparison as quantitative as possible, we have averaged the theoretical results over Frank-Condon, intensity, and rotational distributions to best match the experimental conditions. Rotational motion in H$_{2}^+$ is found to be important even for ultrashort pulses ranging from 10-45fs FWHM.