uv-laser photofragmentation of a 2-MeVH2+beam

A 2-MeV beam of ${\mathrm{H}}_2^{+}$ molecular ions was excited by 193-nm photons from an ArF laser. The ${\mathrm{H}}^{+}$ photofragments were energy analyzed by an electrostatic analyzer, and the potential energy released in the ${\mathrm{H}}_2^{+}$ rest frame was determined. The released energy corresponds to absorption from low-lying vibrational levels of the $1s{\sigma }_g$ ground state to the $2p{\sigma }_u$ state of ${\mathrm{H}}_2^{+}$.