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arXiv · 1809.04108

Rediscovering the Tidal Tails of NGC 288 with Gaia DR2

Shaziana Kaderali·Jason A. S. Hunt·Jeremy J. Webb·Natalie Price-Jones·Raymond Carlberg
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Abstract

NGC 288 is a Galactic globular cluster having observed extra tidal structure, without confirmed tidal tails. $Gaia$ DR2 provides photometric and astrometric data for many of the stars in NGC 288 and its extra tidal structure. To compare with $Gaia$ data, we simulate an $N$-body model of a star cluster with the same orbit as NGC 288 in a Milky Way potential. The simulation shows that the cluster forms tidal tails that are compressed along the cluster's orbit when it is at apocentre and are expected to be a diffuse bipolar structure. In this letter, we present a comparison between the simulation and observations from $Gaia$ DR2. We find that both the simulation and the observations share comparable trends in the position on the sky and proper motions of the extra-tidal stars, supporting the presence of tidal tails around NGC 288.

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Shaziana Kaderali, Jason A. S. Hunt, Jeremy J. Webb, Natalie Price-Jones, Raymond Carlberg. 2018-09-11. Rediscovering the Tidal Tails of NGC 288 with Gaia DR2. https://doi.org/10.1093/mnrasl%2Fslz015

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