Coffee talks
Friday 06/10/2023 @ 11:30, Sala seminari OAS (area CNR) secondo piano e on-line (meet.google.com/sue-bwvk-axf)
Yue Hu (University of Wisconsin–Madison, USA), "Magnetic Fields in Galaxy Clusters: Insights from Synchrotron and X-Ray Intensity Gradients"
Magnetic fields and their dynamical interplay with matter in galaxy clusters contribute to the physical properties and evolution of the ICM. However, current understanding of the origin and properties of cluster magnetic fields is still limited by observational challenges. I will show that the Synchrotron Intensity Gradient (SIG) and X-ray Intensity Gradient (XIG) are closely linked to magnetic fields, offering an promising method to map these fields. Specifically, for clusters RXC J1314.4 -2515 and Abell 2345, the magnetic fields derived from SIG within radio relics align remarkably well with those discerned via synchrotron polarization. Notably, SIG surpasses the limitations set by Faraday depolarization, facilitating the mapping of magnetic fields within radio halos. I will present the magnetic field maps for the halos of RXC J1314.4 -2515 and El Gordo. Magnetic fields in radio halos are found to exhibit a preferential direction along the major merger axis. These findings are consistent with the pictures that turbulent magnetic fields in cluster mergers that are stirred and amplified by matter motions. Moreover, I will show that beyond SIG, XIG can advantageously map magnetic fields associated with thermal gas.