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Galaxy Disruption Caught in the Act

A. M. Karick·M. J. Drinkwater·M. West·M. D. Gregg·M. Hilker
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Abstract

Direct evidence of stellar material from galaxy disruption in the intra-cluster medium (ICM) relies on challenging observations of individual stars, planetary nebulae and diffuse optical light. Here we show that the ultra-compact dwarf galaxies (UCDs) we have discovered in the Fornax Cluster are a new and easy-to-measure probe of disruption in the ICM. We present spectroscopic observations supporting the hypothesis that the UCDs are the remnant nuclei of tidally ``threshed'' dwarf galaxies. Deep optical imaging of the cluster has revealed a 43-kpc long arc of tidal debris, flanking a nucleated dwarf elliptical (dE,N) cluster member. We may be witnessing galaxy threshing in action.

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A. M. Karick, M. J. Drinkwater, M. West, M. D. Gregg, M. Hilker. 2003-10-16. Galaxy Disruption Caught in the Act. https://arxiv.org/abs/astro-ph/0310448

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