The absorption spectrum of the Hartley band of ozone in a cold molecular beam has been investigated using a hole-burning depletion technique over the wavelength range 273.2-284 mn. This spectrum shows a more pronounced vibrational structure than the corresponding absorption spectrum measured at similar to200 K which is often used as a reference for the quality of ab initio calculations. Comparison of the depletion spectrum with the wavelength-dependent fluctuation of the vibrational state distribution of the photogragment O-2((1)Delta(g)) indicates that this fluctuation is to a significant extent due to an interference effect.