We can approximate the final observable action spectroscopy signal as I(ν)•f (ν), where I(ν) is the absorption spectrum of the molecule and f (ν) is the quantum yield of the dissociation. The general form of the damping function f (ν) from Equation 13 is given in Figure . Application of this function effectively zeroes signals with energies below the threshold (hν < D). Signals above the threshold are scaled by factors, increasing with the increase of the photon energy hν. ).