Speaker: Susanna Barsanti (University College Dublin)
Title: Detecting scalar fields with EMRIs: the effects of gravitational post-adiabatic corrections
Abstract: Asymmetric binaries, i.e. compact binary systems with a large mass asymmetry, such as Extreme Mass Ratio Inspirals (EMRIs), are key sources for the future space detector LISA. Inspiralling around the central black hole (the primary), the smaller object (the secondary) generates gravitational waves (GWs) that harbour the potential for precise tests of fundamental physics. In this talk, I will focus on a model of asymmetric binaries in theories of gravity with new fundamental scalar fields, where the primary scalar charge per unit mass is suppressed, so that the background spacetime is simply described by the Kerr metric. Moreover, at leading - adiabatic - order in the binary mass ratio, the imprint of the scalar field on the emitted waveform is fully captured by an extra parameter: the scalar charge per unit mass carried by the secondary. I will show how this parameter affects the emitted GWs and, by analysing such signals, I will present the encouraging results on the LISA ability to detect the scalar charge. Finally, I will present the latest results arising from the inclusion of post-adiabatic corrections in the gravitational sector, and discuss their impact on the scalar field detectability.
Room: Sala de Reuniões e Seminários (2-8.3, 2nd Floor of Physics Building)