Echos in the Dark: Gravitational waves from colliding ECOs at Atom Interferometers

<!--HTML--><p>Long-baseline atom interferometers offer an exciting opportunity to explore mid-frequency gravitational waves (GW). In this lecture we will survey the landscape of possible contributions to the total ‘gravitational wave background’ within this frequency band. Crucially we will find that the inspiral phases of stellar-mass compact binary systems cumulatively produce a signal well within reach of the proposed AION-km and AEDGE experiments. Not only will this form a relevant background to searches for other sources of GW at these experiments, but it constitutes an interesting signal in its own right which may have much to reveal about the Universe. We will further show that hypothetical populations of dark sector exotic compact objects such as fermion and boson stars could generate signatures unique to mid- and low-frequency gravitational wave detectors, providing a novel means to probe complexity in the dark sector.</p><p><strong>About the speaker</strong>&nbsp;<br><span style="color:hsl(210,75%,60%);"><strong>Hannah Banks</strong></span> is a PhD student at the Department for Applied Mathematics and Theoretical Physics at the University of Cambridge. She was lucky enough to spend a year at CERN on the Doctoral Students Programme within the QTI-TH branch.</p><p><strong>Collaborators:</strong> Matthew McCullough, Dorota Grabowska.</p>