Experimental Evidence of an Interference between Photodissociation Continua

The two states ¹Σᵤ⁺ B and B^' of H₂, dissociating adiabatically to H(2p)+H(1s) and H(2s)+H(1s), respectively, are simultaneously excited by vacuum-ultraviolet photon absorption, above threshold. The combination of the coherent excitation of the two continua and of a nonadiabatic transition occurring at large internuclear distance produces a quantum interference effect in the partial photodissociation cross section which strongly affects the branching ratio ${{{σ}}ₚ({H}₂{→}H(2p)+H(1s))}{{{σ}}ₛ({H}₂{→}H(2s)+H(1s))}$. Comparisons with theoretical predictions are presented and discussed.