Horizon-absorption effects in coalescing black-hole binaries: An effective-one-body study of the nonspinning case


We study the horizon absorption of gravitational waves in coalescing, circularized, nonspinning black-hole binaries. The horizon-absorbed fluxes of a binary with a large mass ratio (q= 1000) obtained by numerical perturbative simulations are compared with an analytical, effective-one-body (EOB) resummed expression recently proposed. The perturbative method employs an analytical, linear in the mass ratio, EOB-resummed radiation reaction, and the Regge-Wheeler-Zerilli formalism for wave extraction. Hyperboloidal layers are employed for the numerical solution of the Regge-Wheeler-Zerilli equations to accurately compute horizon fluxes up to the late plunge phase. The horizon fluxes from perturbative simulations and the EOB-resummed expression agree at the level of a few percent down to the late plunge. An upgrade of the EOB model for nonspinning binaries that includes horizon absorption of angular …

Physical Review D