DECam photometry reveals extra-tidal stars around the Milky Way globular cluster NGC 6864 (M75)
arXiv:2111.02496 · doi:10.1093/mnras/stab3238
Abstract
Globular clusters are prone to lose stars while moving around the Milky Way. These stars escape the clusters and are distributed throughout extended envelopes or tidal tails. However, such extra-tidal structures are not observed in all globular clusters, and yet there is no structural or dynamical parameters that can predict their presence or absence. NGC\,6864 is an outer halo globular cluster with reported no observed tidal tails. We used Dark Energy Camera (DECam) photometry reaching 4 mag underneath its main sequence turnoff to confidently detect an extra-tidal envelope, and stellar debris spread across the cluster outskirts. These features emerged once robust field star filtering techniques were applied to the fainter end of the observed cluster main sequence. NGC\,6864 is associated to the {\it Gaia}-Enceladus dwarf galaxy, among others 28 globular clusters. Up-to-date, nearly 64 of them have been targeted looking for tidal tails and most of them have been confirmed to exhibit tidal tails. Thus, the present outcomes allow us to speculate on the possibility that {\it Gaia}-Enceladus globular clusters share a common pattern of mass loss by tidal disruption.
9 pages, 7 figures. Accepted for publication in MNRAS
References in corpus (21)
- Detection of a 63 Degree Cold Stellar Stream in the Sloan Digital Sky Survey
- Reconstructing the Last Major Merger of the Milky Way with the H3 Survey
- Reverse engineering the Milky Way
- A 22 Degree Tidal Tail for Palomar 5
- A comprehensive Nbody study of mass segregation in star clusters: Energy equipartition and escape
- Orbital Clustering Identifies the Origins of Galactic Stellar Streams
- Globular cluster number density profiles using Gaia DR2
- Variations in the width, density, and direction of the Palomar 5 tidal tails
- A search for stellar tidal debris of defunct dwarf galaxies around globular clusters in the inner Galactic halo
- On the tidal tails of Milky Way globular clusters
- Stellar envelopes of globular clusters embedded in dark mini-haloes
- The dynamics of the globular cluster NGC3201 out to the Jacobi radius
- Spherical models of star clusters with potential escapers
- Star cluster formation history along the minor axis of the Large Magellanic Cloud
- Extra-tidal structures around the Gaia Sausage candidate globular cluster NGC6779 (M56)
- Detection of a diffuse extended halo-like structure around 47 Tuc
- Stellar cluster candidates discovered in the Magellanic System
- Effects of chaos on the detectability of stellar streams
- Signatures of tidal disruption in the Milky Way globular cluster NGC 6981 (M72)
- Testing for Dark Matter in the Outskirts of Globular Clusters
- Absence of obvious tidal tails around the globular cluster NGC 6397