Spectroscopic hint of a cold stream in the direction of the globular cluster NGC 1851
We present the results of a spectroscopic survey performed in the outskirts of the globular cluster NGC 1851 with VIsible MultiObject Spectrograph (VIMOS)/Very Large Telescope (VLT). The radial velocities of 107 stars in a region between 12 and 33arcmin around the cluster have been derived. We clear...
| Autores: | , , , , , , , |
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| Tipo de recurso: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2012 |
| País: | España |
| Institución: | Consejo Superior de Investigaciones Científicas (CSIC) |
| Repositorio: | DIGITAL.CSIC. Repositorio Institucional del CSIC |
| OAI Identifier: | oai:digital.csic.es:10261/424816 |
| Acceso en línea: | http://hdl.handle.net/10261/424816 |
| Access Level: | acceso abierto |
| Palabra clave: | Methods: data analysis Methods: observational Techniques: radial velocities Globular clusters: individual: NGC 1851 Galaxy: halo Galaxy: stellar content |
| Sumario: | We present the results of a spectroscopic survey performed in the outskirts of the globular cluster NGC 1851 with VIsible MultiObject Spectrograph (VIMOS)/Very Large Telescope (VLT). The radial velocities of 107 stars in a region between 12 and 33arcmin around the cluster have been derived. We clearly identify the cluster stellar population over the entire field of view, indicating the presence of a significant fraction of stars outside the tidal radius predicted by King models. We also find tentative evidence of a cold (σv ≤ 20kms-1) peak in the distribution of velocities at vr ∼ 180kms-1 constituted mainly by main-sequence stars whose location in the colour-magnitude diagram is compatible with a stream at a similar distance to this cluster. If confirmed, this evidence would strongly support the extragalactic origin of this feature. © 2012 The Authors Monthly Notices of the Royal Astronomical Society © 2012 RAS. |
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