Current and anticipated acceleration linear (acc. lin.) spectral density of an atom interferometer enhanced by an optomechanical resonator. Current intrinsic performance (blue dash-dotted line) is achieved using a T = 10 ms interferometer with cycle frequency fc = 0.6 Hz, momentum separation of two photon recoils and residual technical noise of 30 mrad. It can be improved with a pulse separation time T = 35 ms, a cycle frequency fc = 1 Hz, momentum separation of eight photon recoils and residual phase noise 3 mrad (orange dash-dotted line). Similarly, current optomechanical resonator acceleration sensitivity at quiet conditions (solid blue curve) with a resonance of 678.5 Hz and optical finesse 2 can be optimised by choosing a resonance frequency of 1500 Hz and finesse of 1600 (solid orange curve). Dashed lines indicate the intrinsic noise of the optomechanical resonator weighted by the sensitivity function of the atom interferometer and high-pass filtered at 0.8 Hz (1 Hz) for the current (advanced) scenario to suppress additional noise in the low-frequency band. The shaded areas bounded by fc (discs) and the atom interferometer’s corner frequency (triangles) mark the respective dominant frequency bands most relevant for optimal postcorrection of seismic noise, and motivate high-pass filtering the resonator signal (light blue and orange solid lines).