The Effect of Age on the Grouping of Open Clusters : II. Are There Old Binary Clusters?
Casado Giménez, Juan (Universitat Autònoma de Barcelona. Departament de Química)

Fecha:	2022
Resumen:	In the present study, we continue testing the Primordial Group hypothesis (Casado 2022), which postulates that only sufficiently young open clusters can be binary or multiple, and old clusters are essentially single. To this end, we revisit all the remaining binary cluster candidates in the Galaxy having at least one cluster older than 100 Myr through Gaia data and careful revision of the literature. We found no convincing case for an old binary system among the 120 pairs/groups revised. Most of the pairs are optical pairs or flyby encounters. However, we found three dubious pairs that could falsify the title hypothesis upon further research. We also found two possible primordial pairs older than expected. Our results confirm that the vast majority of binary/multiple OCs in the Galaxy, if not all, are of primordial origin and are not stable for a long time. This finding is in line with similar studies of the Magellanic Clouds and theoretical N-body simulations in the Galaxy. The pairs of OCs in these groups are generally not binary systems since they are not gravitationally bound. We also point out some inconsistencies in previous works and databases, such as false open clusters and duplicities.
Nota:	Thanks to Alfred Castro Ginard for providing updated astrophysical parameters and figures of some of the OCs studied. This work made use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/Gaia, accessed on 7 October 2021), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/Gaia/ dpac/consortium, accessed on 7 October 2021). Funding for the DPAC was provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement. This research made extensive use of the SIMBAD database and the VizieR catalogue access tool, operating at the CDS, Strasbourg, France (DOI: 10.26093/cds/vizier), and of NASA Astrophysics Data System Bibliographic Services.
Derechos:	Aquest document està subjecte a una llicència d'ús Creative Commons. Es permet la reproducció total o parcial, la distribució, la comunicació pública de l'obra i la creació d'obres derivades, fins i tot amb finalitats comercials, sempre i quan es reconegui l'autoria de l'obra original.
Lengua:	Anglès
Documento:	Article ; recerca ; Versió publicada
Publicado en:	Universe, Vol. 8 Núm. 7 (July 2022) , art. 368, ISSN 2218-1997

DOI: 10.3390/universe8070368

23 p, 1.1 MB

El registro aparece en las colecciones:
Artículos > Artículos de investigación
Artículos > Artículos publicados