Speaker
Description
I will present different possibilities to discover close small mass ratio inspirals (SMRI) based on the EM variability of the nucleus prior to the merger. The secondary object ($m$), which is several orders of magnitude less massive than the primary supermassive black hole ($M$), i.e. the mass ratio $q = m/M = 10^{-2} - 10^{-8}$, orbits around the primary while transiting through the environment in the vicinity of the SMBH. In the strong gravity regime, the secondary completes about $\sim q^{-1}$ orbits around the primary, with the total duration of the inspiral ranging from weeks to decades. Such inspirals are expected to be one of the main sources of signal for the upcoming space-based gravitational-wave observatory LISA. I will show the possible observational manifestation of such system in the EM spectrum taking into account the repetitive interaction of the secondary with the accreting plasma.