Journal of High Energy Physics (Dec 2024)
Dynamics of spinning binary at 2PM
Abstract
Abstract We consider the covariant proposal for the gravitational Compton amplitude for a Kerr black hole. Employing the covariant three- and four-point Compton amplitudes, we assemble the classical one-loop integrand on the maximal cut at all orders in spin, utilizing the method of unitarity. Expanding in powers of spin, we evaluate the one-loop amplitude up to O G 2 a 8 $$ \mathcal{O}\left({G}^2{a}^8\right) $$ . Supplemented with extra contact contributions derived from the far-zone data of the Teukolsky solutions, the one-loop amplitude is in agreement with results available in the literature. We showcase the classical eikonal in the aligned-spin case at O G 2 a 7 $$ \mathcal{O}\left({G}^2{a}^7\right) $$ .
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