Identification of the long stellar stream of the prototypical massive globular cluster ω Centauri

Journal
Date Issued
2019
Author(s)
Ibata, Rodrigo A.
•
•
Malhan, Khyati
•
Martin, Nicolas
•
Bianchini, Paolo
DOI
Abstract
Omega Centauri (ω Cen) is the Milky Way's most massive globular cluster, and has long been suspected of being the remnant core of an accreted dwarf galaxy. If this scenario is correct, ω Cen should be tidally limited and tidal debris should be spread along its orbit. Here we use N-body simulations to show that the recently discovered `Fimbulthul' structure is the long-sought-for tidal stream of ω Cen, extending up to 28° from the cluster. Follow-up high-resolution spectroscopy of five stream stars shows that they are closely grouped in velocity, and have metallicities consistent with having originated in that cluster. Informed by our N-body simulations, we devise a selection filter that we apply to Gaia mission data to also uncover the stream in the highly contaminated and crowded field within 10° of ω Cen. Further modelling of the stream may help to constrain the dynamical history of the dwarf galaxy progenitor of this disrupting system and guide future searches for its remnant stars in the Milky Way.
Volume
3
Start page
667
Uri
Url
Issn Identifier
2397-3366
Ads BibCode
2019NatAs...3..667I
Rights
open.access
File(s)
Loading...
Thumbnail Image
Name

preprint 1902.09544.pdf

Description
preprint
Size

1.61 MB

Format

Adobe PDF

Checksum (MD5)

76b682a455129514e8f0940ecfe94c7f

Loading...
Thumbnail Image
Name

s41550-019-0751-x.pdf

Description
[Administrators only]
Size

2.65 MB

Format

Adobe PDF

Checksum (MD5)

33f4f4adc2db96ca58adfa5da912ace9