PUB - Publikationen an der Universität Bielefeld

On a time scale of years to decades, gravitational wave (GW) astronomy willbecome a reality. Low frequency (nanoHz) GWs are detectable through long-termtiming observations of the most stable pulsars. Radio observatories worldwideare currently carrying out observing programmes to detect GWs, with data setsbeing shared through the International Pulsar Timing Array project. One of themost likely sources of low frequency GWs are supermassive black hole binaries(SMBHBs), detectable as a background due to a large number of binaries, or ascontinuous or burst emission from individual sources. No GW signal has yet beendetected, but stringent constraints are already being placed on galaxyevolution models. The SKA will bring this research to fruition. In this chapter, we describe how timing observations using SKA1 willcontribute to detecting GWs, or can confirm a detection if a first signalalready has been identified when SKA1 commences observations. We describe howSKA observations will identify the source(s) of a GW signal, search foranisotropies in the background, improve models of galaxy evolution, testtheories of gravity, and characterise the early inspiral phase of a SMBHBsystem. We describe the impact of the large number of millisecond pulsars to bediscovered by the SKA; and the observing cadence, observation durations, andinstrumentation required to reach the necessary sensitivity. We describe thenoise processes that will influence the achievable precision with the SKA. Weassume a long-term timing programme using the SKA1-MID array and consider theimplications of modifications to the current design. We describe the possiblebenefits from observations using SKA1-LOW. Finally, we describe GW detectionprospects with SKA1 and SKA2, and end with a description of the expectations ofGW astronomy.