A dynamical evolution study of 40 2MASS open clusters
Autor: | Yüksel Karataş, Charles Jose Bonatto, Orhan Güneş |
---|---|
Rok vydání: | 2017 |
Předmět: |
Physics
Initial mass function 010308 nuclear & particles physics FOS: Physical sciences Astronomy and Astrophysics Radius Astrophysics Astrophysics - Astrophysics of Galaxies 01 natural sciences Flattening Stars Space and Planetary Science Astrophysics of Galaxies (astro-ph.GA) 0103 physical sciences Cluster (physics) Relaxation (physics) Mass segregation 010303 astronomy & astrophysics Astrophysics::Galaxy Astrophysics Open cluster |
Zdroj: | Astronomische Nachrichten. 338:464-488 |
ISSN: | 1521-3994 0004-6337 |
DOI: | 10.1002/asna.201712978 |
Popis: | We investigate the dynamical evolution of 40 open clusters (OCs) by means of their astrophysical parameters derived from field-decontaminated 2MASS photometry. We find a bifurcation in the planes core radius vs. age and cluster radius vs. age, in which part of the clusters appear to expand with time probably due to the presence of stellar black holes while others seem to shrink due to dynamical relaxation. Mass functions (MFs) are built for 3$/$4 of the sample (31 OCs), which are used to search for indications of mass segregation and external dynamical processes by means of relations among astrophysical, structural and evolutionary parameters. We detect a flattening of MF slopes ocurring at the evolutionary parameters $\tau_{core}\leq 32$ and $\tau_{overall}\leq 30$, respectively. Within the uncertainties involved, the overall MF slopes of 14 out of 31 OCs with $m_{overall} > 500~M_{\odot}$ are consistent with Kroupa's initial mass function, implying little or no dynamical evolution for these clusters. The remaining 17 OCs with MF slopes departing from that of Kroupa show mild/large scale mass segregation due to dynamical evolution. Comment: Accepted by AN. 48 pages, 36 figures and 11 tables |
Databáze: | OpenAIRE |
Externí odkaz: |