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arXiv · 2110.12297

On the detection of multiple shock fronts in A1914 using deep Chandra X-ray observations

Abstract

Here, we report the new detection of three shock fronts using archival \textit{Chandra} X-ray observations in Abell 1914, which also hosts a radio halo, a radio phoenix, and a head-tail galaxy. In this study, we report the X-ray shock front at the position of the radio phoenix, which further strengthens the scenario that radio phoenix traces old plasma that gets lit up when compressed by shock passage. We further analyze the thermodynamic structure of the cluster in detail. We create temperature maps of A1914 using three different techniques, Adaptive Circular Binning (ACB), Weighted Voronoi Tessellations (WVT), and Contour binning (Contbin) method. These thermodynamic maps, along with the pseudo pressure and the pseudo entropy maps for the cluster, are evidence of disturbed morphology produced by multiple merger events. These merger events create cluster-wide turbulence, which may re-accelerate the relativistic particles and result in a radio halo within the cluster. Further, comparing X-ray and radio images reveals that the radio halo is contained within two X-ray shock fronts. Our analysis suggests that A1914 has both equatorial shock and axial shock within the cluster's ICM. We proposed a dual merging scenario based on the shock position and analysis of the thermodynamic maps obtained from the deeper \textit{Chandra} X-ray observations.

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Majidul Rahaman, Ramij Raja, Abhirup Datta. 2021-10-23. On the detection of multiple shock fronts in A1914 using deep Chandra X-ray observations. https://doi.org/10.1093/mnras%2Fstab3115

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