Volume 375, Number 3, September 2001
|Page(s)||840 - 850|
|Section||Galactic structure, stellar clusters, and populations|
|Published online||15 September 2001|
Structure and mass function of five intermediate/old open clusters
State Observatory, Manora Peak, Naini Tal -263 129, Uttaranchal, India e-mail: alok,firstname.lastname@example.org
Corresponding author: A. K. Durgapal, email@example.com
Accepted: 30 May 2001
The UBVRI data of five northern open star clusters are used to study the mass function (MF), structure and dynamical state of these clusters. The clusters under discussion have ages ranging from ~0.6 to 5 Gyr. A comparison of the density profiles indicates that the evolution of the core of these clusters is almost the same, whereas the corona of the clusters are probably affected by the external environment and dynamical evolution. For the entire cluster region, the slope of the MF of three clusters (Be 64, Be 69 and King 5) has a value that agrees within the error with the Salpeter value, whereas King 7 and Be 20 show a steeper () and almost a flat MF respectively. We find that the slope of the MF of two clusters (King 5 and King 7) changes significantly from the inner region to the outer region, becoming steeper at larger radii. The dynamical relaxation time of the clusters under discussion is less than the age of the clusters, which indicates that all of these clusters are dynamically relaxed. Thus the observed mass segregation in three clusters can be attributed to the dynamical evolution of the clusters. The ratio of the clusters' present radius to the limiting radius (determined from the relation given by King [CITE]) can be representated by an exponent law.
Key words: galaxy: open clusters and associations: general
© ESO, 2001
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.