| Title: |
The Gaia-ESO Survey: Asymmetric expansion of the Lagoon Nebula cluster NGC 6530 from GES and Gaia DR2 |
| Authors: |
Wright, NJ; Jeffries, RD; Jackson, RJ; Bayo, A; Bonito, R; Damiani, F; Kalari, V; Lanzafame, AC; Pancino, E; Parker, RJ; Prisinzano, L; Randich, S; Vink, JS; Alfaro, EJ; Bergemann, M; Franciosini, E; Gilmore, G; Gonneau, A; Hourihane, A; Jofré, P; Koposov, SE; Lewis, J; Magrini, L; Micela, G; Morbidelli, L; Sacco, GG; Worley, CC; Zaggia, S |
| Publisher Information: |
Oxford University Press https://academic.oup.com/mnras/article/486/2/2477/5420759#134046197 Monthly Notices of the Royal Astronomical Society 2019-07-15T09:43:13Z 2019-07-15T09:43:13Z 2019-06-01 |
| Document Type: |
Electronic Resource |
| Abstract: |
The combination of precise radial velocities from multi-object spectroscopy and highly accurate proper motions from Gaia DR2 opens up the possibility for detailed 3D kinematic studies of young star-forming regions and clusters. Here, we perform such an analysis by combining Gaia-ESO Survey spectroscopy with Gaia astrometry for ∼900 members of the Lagoon Nebula cluster, NGC 6530. We measure the 3D velocity dispersion of the region to be 5.35+0.39 -0.34 km s-1, which is large enough to suggest the region is gravitationally unbound. The velocity ellipsoid is anisotropic, implying that the region is not sufficiently dynamically evolved to achieve isotropy, though the central part of NGC 6530 does exhibit velocity isotropy that suggests sufficient mixing has occurred in this denser part. We find strong evidence that the stellar population is expanding, though this is preferentially occurring in the declination direction and there is very little evidence for expansion in the right ascension direction. This argues against a simple radial expansion pattern, as predicted by models of residual gas expulsion. We discuss these findings in the context of cluster formation, evolution, and disruption theories.; NJW acknowledges an STFC Ernest Rutherford Fellowship (grant number ST/M005569/1). RJP acknowledges support from the Royal Society in the form of a Dorothy Hodgkin Fellowship. AB acknowledges support from ICM (Iniciativa Científica Milenio) via the Núcleo Milenio de Formación Planetaria. EJA acknowledges support from the Spanish Government Ministerio de Ciencia, Innovacion y Universidades though grant AYA2016-75 931-C2-1 and from the State Agency for Research of the Spanish MCIU through the ‘Center of Excellence Severo Ochoa’ award for the Instituto de Astrofisica de Andalucia (SEV-2017-0709). |
| Index Terms: |
stars: formation; stars: kinematics and dynamics; open clusters and associations: individual: Lagoon Nebula, NGC 6530, M8; Article |
| URL: |
https://www.repository.cam.ac.uk/handle/1810/294610 |
| Availability: |
Open access content. Open access content |
| Note: |
application/pdf; English |
| Other Numbers: |
HS1 oai:www.repository.cam.ac.uk:1810/294610; 1487960583 |
| Contributing Source: |
UNIV OF CAMBRIDGE; From OAIster®, provided by the OCLC Cooperative. |
| Accession Number: |
edsoai.on1487960583 |
| Database: |
OAIster |