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arXiv · 2604.27902

The Complex Structure of the Abell 548 - Abell 3367 Region

Mark J. Henriksen·Layla Ahmed
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Abstract

Archival XMM and ROSAT X-ray data are used to investigate the structure of the Abell 548 - Abell 3367 region. Based on previous optical studies, this is a region likely to be rich in structure though studies are in disagreement regarding the connection between Abell 3367 and Abell 548. We use the available archival X-ray data together with kinematic data of counterpart galaxies to address this question and to determine the structure in this region. The region is particularly rich in X-ray structure elongated along a SW-NE axis consisting of numerous extended X-ray sources. In general, the structure consists of many galaxy groups and clusters which appear segregated in X-ray luminosity with the least luminous $\sim$ 30% toward the outer region of the clusters, possibly tracing a filament. We find evidence to suggest a supercluster of 3 clusters at redshifts: $\sim$ 0.04, 0.045, and 0.06. Some of the X-ray sources coincident with Abell 3367 have counterpart galaxy redshifts consistent with Abell 548 and others are significantly higher. This supports that Abell 548 and Abell 3667, form a supercluser and the higher redshift X-ray source is a background object. They are part of a larger structure consisting of a previously identified cluster at redshift 0.04, and two groups at redshift $\sim$ 0.06. In addition, there is a filamentary structure at z $\sim$ 0.103. The ubiquity of groups in the large scale structure suggests that they provide an environment where galaxies are in close proximity and evolution via interaction can proceed well before the galaxies make their way into the dense central region of a cluster.

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Mark J. Henriksen, Layla Ahmed. 2026-04-30. The Complex Structure of the Abell 548 - Abell 3367 Region. https://doi.org/10.3390/astronomy3040018

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