## Accurate modeling of intermediate-mass-ratio inspirals: exploring the form of the self-force in the intermediate-mass-ratio regime

by **Huerta, E. A.** and **Kumar, Prayush** and **Brown, Duncan A.**

21 pages, 8 figures. Submitted to PRD

The LIGO detector is undergoing a major upgrade that will increase its sensitivity by a factor of 10, and extend its bandwidth from 40 Hz to 10 Hz on the lower frequency end, while also allowing for high-frequency operation due to its tunability. This advanced LIGO (aLIGO) detector will extend the mass range at which compact mass binaries may be detected by a factor of four or more at a fixed signal-to-noise ratio [1]. The inspirals of stellar-mass compact objects into intermediate-mass black holes (IMBHs) of 50-350 solar masses will lie in the frequency band of aLIGO [2]. GW searches for these type of events will provide conclusive evidence for the existence of IMBHs and explore the dynamics of cluster environments. To realize this science we need to develop waveform templates that accurately capture the dynamical evolution of these type of events before aLIGO begins observations. Implementing gravitational self-force (SF) corrections in templates for compact binaries with mass-ratios 1:10-1:1000 will be essential to decode the information contained in the GW signals emitted by these sources. However, these SF corrections have been computed for low-frequency events with extreme mass-ratios 1:10^4-1:10^7. We develop a waveform model that accurately reproduces the dynamical evolution of intermediate mass ratio inspirals, as predicted by the effective-one-body (EOB) model introduced in [3], and which enables us to shed some light on the form of the SF for events with mass-ratio 1:6, 1:10 and 1:100. To complement this study, we make use of SF results in the extreme-mass-ratio regime, and of predictions of the EOB model introduced in [3], to derive a prescription for the shift of the orbital frequency at the innermost stable circular orbit which consistently captures predictions from the extreme, intermediate and comparable mass-ratio regimes.