Detection of a diffuse extended halo-like structure around 47 Tuc

Abstract

We constructed for the first time a stellar density profile of 47 Tucanae (47 Tuc) out of $\sim$ 5.5 times its tidal radius ($r_t$) using high-quality deep $BV$ photometry. After carefully considering the influence of photometric errors, and Milky Way and Small Magellanic Cloud composite stellar population contamination, we found that the cluster stellar density profile reaches a nearly constant value from $\sim$ 1.7$r_t$ outwards, which does not depend on the direction from the cluster's center considered. These results visibly contrast with recent distinct theoretical predictions on the existence of tidal tails or on a density profile that falls as $r^{-4}$ at large distances, and with observational outcomes of a clumpy structure as well. Our results suggest that the envelope of 47 Tuc is a halo- like nearly constant low density structure.

6 pages, 4 figures. Accepted for publication in the Astrophysical Journal Letters

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Cited by in corpus (5)

• On the tidal tails of Milky Way globular clusters
• The e-TidalGCs Project: Modeling the extra-tidal features generated by Galactic globular clusters
• Extra-tidal structures around the Gaia Sausage candidate globular cluster NGC6779 (M56)
• On the extended stellar structure around NGC 288
• Revisiting newly Large Magellanic Cloud age gap star clusters