Revisiting gravitational angular momentum and mass dipole losses in the eikonal framework

Abstract

We review the description of classical gravitational scatterings of two compact objects by means of the eikonal framework. This encodes via scattering amplitudes both the motion of the bodies and the gravitational-wave signals that such systems produce. As an application, we combine the next-to-leading post-Minkowskian waveform derived in the post-Newtonian PN limit with the 4PM static loss due to the linear memory effect to reproduce known results for the total angular momentum loss in the center-of-mass frame up to and 2.5PN order. We also provide similar expressions for the change in the system’s mass dipole, discussing the subtleties related to its sensitivity to the Coulombic components of the field and to the nonlinear memory effect.