Dynamic Tidal Alignment of Cluster Galaxies
نویسنده
چکیده
We investigate the role of parametric tidal interactions between cluster galaxies and the cluster potential by considering galaxy and cluster dynamical properties and drawing an analogy between these systems and the Milky Way-dSph system. We suggest that some cluster galaxies are indeed undergoing resonant excitation and argue that this will cause a tendency for alignment of the galaxies’ long axis along the radial direction (towards the cluster center). We look for this signature in a sample of 70 x-ray selected clusters observed by the Sloan Digital Sky Survey, and find robust statistical evidence for the existence of a radial alignment mechanism. Subject headings: galaxies: elliptical — Galaxy: evolution — galaxies: kinematics and dynamics
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Radial Alignment of Cluster Galaxies
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