Highly dynamically evolved intermediate-age open clusters

DOI: 
10.1093/mnras/stw3154
Publication date: 
01/04/2017
Main author: 
Piatti, Andrés E.
IAA authors: 
Sampedro, Laura M.
Authors: 
Piatti, Andrés E.;Dias, Wilton S.;Sampedro, Laura M.
Journal: 
Monthly Notices of the Royal Astronomical Society
Refereed: 
Yes
Publication type: 
Article
Volume: 
466
Pages: 
392-406
Abstract: 

We present a comprehensive UBVRI and Washington CT<SUB>1</SUB>T<SUB>2</SUB> photometric analysis of seven catalogued open clusters, namely: Ruprecht 3, 9, 37, 74, 150, ESO 324-15 and 436-2. The multiband photometric data sets in combination with 2MASS photometry and Gaia astrometry for the brighter stars were used to estimate their structural parameters and fundamental astrophysical properties. We found that Ruprecht 3 and ESO 436-2 do not show self-consistent evidence of being physical systems. The remained studied objects are open clusters of intermediate age (9.0 ≤ log(t yr<SUP>-1</SUP>) ≤ 9.6), of relatively small size (r<SUB>cls</SUB> ̃ 0.4-1.3 pc) and placed between 0.6 and 2.9 kpc from the Sun. We analysed the relationships between core, half-mass, tidal and Jacoby radii as well as half-mass relaxation times to conclude that the studied clusters are in an evolved dynamical stage. The total cluster masses obtained by summing those of the observed cluster stars resulted to be ̃10-15 per cent of the masses of open clusters of similar age located closer than 2 kpc from the Sun. We found that cluster stars occupy volumes as large as those for tidally filled clusters.

Database: 
ADS
SCOPUS
URL: 
https://www.scopus.com/inward/record.uri?eid=2-s2.0-85018255345&doi=10.1093%2fmnras%2fstw3154&partnerID=40&md5=6834c34154a39a0d9dd98d935e1f92d4
ADS Bibcode: 
2017MNRAS.466..392P
Keywords: 
techniques: photometric;open clusters and associations: general;Astrophysics - Astrophysics of Galaxies