Mar 15 – 20, 2020
Europe/Berlin timezone

X-ray spectroscopy of the outskirts of the Perseus Cluster: a shock front near the virial radius

Mar 17, 2020, 5:00 PM


Oral Presentation Clusters and Cosmology II


Ms Zhenlin Zhu (SRON/Leiden University)


Previous X-ray studies of the Perseus Cluster, consisting of 85 Suzaku pointings along eight azimuthal directions, revealed a particularly steep decrease in the deprojected temperature profile near the virial radius r_{200} along the northwest (NW). We have investigated four additional Suzaku observations mapping this region, with a total exposure of ~100 ks. With this deeper data set, designed to have the best possible control of systematic uncertainties, we find that the temperature gradient is indeed much larger than the other seven directions and significantly deviates from the predictions from hydrodynamic simulations. It is noteworthy that the slope of the deprojected temperature profile is not continuous, with a break near r_{200}.We also find a corresponding density jump at a radius of 1.8 Mpc, similar to the location of the temperature break, indicating the presence of a shock front. This potential evidence of a shock front so far away from the cluster center is unprecedented, and may provide a first insight into the properties of large-scale virial shocks which shape the process of galaxy cluster growth. This study serves as a pathfinder for more such features that may be revealed in nearby galaxy clusters, taking advantage of eROSITA’s large field of view, stable background, and improved spatial resolution compared to Suzaku.

Primary author

Ms Zhenlin Zhu (SRON/Leiden University)


Dr Aurora Simionescu (SRON/Leiden University) Dr Hiroki Akamatsu (SRON) Prof. Jelle Kaastra (SRON/Leiden University)

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