Nearly minimum redundant correlator interpolation formula for gravitational wave chirp detection

An absolute lower bound on the number of templates needed to keep the fitting factor above a prescribed minimal value Gamma in correlator-bank detection of (Newtonian) gravitational wave chirps from unknown inspiraling compact binary stars is derived, resorting to the theory of quasi-band-limited functions in the L-infinity norm. An explicit nearly minimum redundant cardinal-interpolation formula for the (reduced, noncoherent) correlator is introduced. Its computational burden and statistical properties are compared to those of the plain lattice of (reduced, noncoherent) correlators, for the same Gamma. An extension to post-Newtonian models is outlined.