Guest: Ayşegül Tümer, MIT
Title: Galaxy Clusters in X-rays and The Future of X-ray Astronomy
Date: December 20, 2023, 13.40-14.30
Location: FENS G025
Abstract: Galaxy clusters host hundreds of galaxies embedded in a hot (~107 — 108 K) and tenuous (~10-5 —10-1 cm-3) plasma, i.e., the intracluster medium (ICM). They are the largest virialized samples of the universe embedded in the deep potential well of a dark matter halo. Mergers of galaxy clusters are the latest stage of the hierarchical formation of large scale structure in the universe, during which shock and cold fronts, turbulence and radio emission structures are formed within the ICM. In addition, cluster formation and evolution are intimately linked to their brightest galaxy cluster (BCG) that host an active galactic nucleus (AGN). While the thermal ICM shines brightly in X-rays, studying the non-thermal processes— such as inverse Compton emission and AGN activity— require information from the hard X-ray regime in addition to radio waveband. Constraining the non-thermal and thermal processes within the ICM, and elucidating the co-evolution of galaxy clusters with their BCGs are crucial to obtain a complete picture of the dynamics of the large scale structure formation and evolution. To observe all these phenomena, taking advantage of the synergies of the X-ray satellites in orbit is necessary. A bigger necessity is that we plan the future X-ray missions in line with the astrophysical mysteries we are witnessing today. I will begin my talk with an introduction of galaxy clusters, their X-ray properties, and how we observe them. I will, then, present the multi-scale/multi-phase galaxy cluster research I conduct using the synergy of our current/past X-ray observatories, i.e., NuSTAR, Chandra, XMM-Newton and Suzaku. Focusing on the X-Ray Imaging and Spectroscopy Mission (XRISM), which we sent to orbit last September, I will finally discuss the most recent and upcoming X-ray missions that have and will have important implications for the future of galaxy cluster science.
Bio: Aysegul Tumer is an observational X-ray astrophysicist. She received her Physics joint Masters and PhD diploma in 2019 from Bogazici University, Turkiye in collaboration with the University of Rome -Tor Vergata, Italy. She worked at the University of Utah Department of Physics and Astronomy as a postdoctoral researcher between 2019-2022 under the supervision of Daniel Wik. She has been continuing her research at MIT Kavli Institute for Astrophysics and Space Research since October 2022 for her second postdoctoral studies working with Marshall Bautz, Michael McDonald and Eric Miller. Her research focuses on the X-ray data analysis of galaxy clusters using NuSTAR, XMM-Newton and Chandra observatories, complemented by radio data. She developed methods for the NuSTAR scattered light background assessment that extended the science scope of the mission. At MIT Kavli, she is expanding her research to the Sunvaey -Zel’dovich study of clusters using The South Pole Telescope (SPT) data, as well as super massive black hole research in cool core galaxy clusters. In June 2023, she officially became an In Flight Calibration Team and Performance Verification Team member of XRISM through her appointment at MIT.