Probing Magnetic Field Morphology in Galaxy Clusters with the Gradient Technique

09/10/2020 - 4:00pm to 5:00pm
Speaker(s) / Presenter(s): 
Yue Hu (University of Wisconsin)
Type of Event (for grouping events):

Magnetic fields in the intracluster medium (ICM) affect the structure and the evolution of galaxy
clusters. However, their properties are largely unknown, and measuring magnetic fields in galaxy
clusters is challenging, especially on large-scales outside of individual radio sources. Here we
probe the plane-of-the-sky orientation of magnetic fields in clusters using the intensity gradients.
The technique is a branch of the Gradient Technique (GT) that employs emission intensity maps
from turbulent gas. We utilize the Chandra X-ray images of the Perseus, M 87, Coma, and
A2597 galaxy clusters, and the VLA radio observations of the synchrotron emission from
Perseus. We find that the fields predominantly follow the sloshing arms in Perseus, which is in
agreement with numerical simulations. The GT-predicted magnetic field shows signatures of
magnetic draping around rising bubbles driven by supermassive black hole (SMBH) feedback in
the centers of cool-core clusters, as well as draping around substructures merging with the Coma

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