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arXiv · 1611.05968

NGC 5523: An Isolated Product of Soft Galaxy Mergers?

Leah M. Fulmer·John S. Gallagher III·Ralf Kotulla
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Abstract

Multi-band images of the very isolated spiral galaxy NGC 5523 show a number of unusual features consistent with NGC 5523 having experienced a significant merger: (1) Near-infrared (NIR) images from the Spitzer Space Telescope (SST) and the WIYN 3.5-m telescope reveal a nucleated bulge-like structure embedded in a spiral disk. (2) The bulge is offset by ~1.8 kpc from a brightness minimum at the center of the optically bright inner disk. (3) A tidal stream, possibly associated with an ongoing satellite interaction, extends from the nucleated bulge along the disk. We interpret these properties as the results of one or more non-disruptive mergers between NGC 5523 and companion galaxies or satellites, raising the possibility that some galaxies become isolated because they have merged with former companions.

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Leah M. Fulmer, John S. Gallagher III, Ralf Kotulla. 2016-11-18. NGC 5523: An Isolated Product of Soft Galaxy Mergers?. https://doi.org/10.1051/0004-6361/201628070

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