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arXiv · 1007.2425

The galaxy alignment effect in Abell 1689: evolution, radial and luminosity dependence

Li-Wei Hung·Eduardo Banados·Roberto De Propris·Michael West
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Abstract

We measure alignments on scales of 1 Mpc $h^{-1}_{71}$ for galaxies in Abell 1689 ($z=0.18$) from an existing Hubble Space Telescope mosaic. We find evidence of galaxy alignment in the inner 500 $h^{-1}_{71}$ kpc. The alignment appears to be stronger towards the centre and is mostly present among the fainter galaxies, while bright galaxies are unaligned. This is consistent with a model where alignments originate from tidal locking.

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Li-Wei Hung, Eduardo Banados, Roberto De Propris, Michael West. 2010-07-14. The galaxy alignment effect in Abell 1689: evolution, radial and luminosity dependence. https://doi.org/10.1088/0004-637x/720/2/1483

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