Dr. Ayşegül Tümer is an observational astrophysicist. Her work focuses on the evolution of galaxy clusters using X-ray data. She studies the thermodynamical properties of the intracluster medium, and galaxy cluster merger tracers such as cold/shock fronts and inverse Compton emission with NuSTAR, XMM-Newton and Chandra X-ray observatories. In addition, she develops methods to assess the instrumental background of NuSTAR.