CCD UBVR PHOTOMETRY OF 2 OLD OPEN CLUSTERS - KING-11 AND BE42 - COMPARISON WITH THEORETICAL-MODELS

DOI: 
Publication date: 
01/04/1991
Main author: 
APARICIO, A
IAA authors: 
APARICIO, A; BERTELLI, G; CHIOSI, C; GARCIAPELAYO, JM
Authors: 
APARICIO, A; BERTELLI, G; CHIOSI, C; GARCIAPELAYO, JM
Journal: 
ASTRONOMY & ASTROPHYSICS SUPPLEMENT SERIES
Publication type: 
Article
Volume: 
88
Pages: 
155-175
Number: 
Abstract: 
In this paper we present the Johnson-Cousins UBVR CCD photometry of the stars in King 11 and Be 42, two open clusters towards the galactic anticenter. We obtain the colour-magnitude (C-M) diagram, the colour excess, the reddening, the metallicity, and the distance modulus of the two clusters. We find that King 11, showing a C-M diagram similar to that of NGC 188 and M 67 ought to have a solar-like metallicity, whereas Be 42 is less metal-rich. The C-M diagram of King 11 is discussed in detail with the aid of models incorporating convective overshoot according to the revised prescription proposed by Aparicio et al. (1990) for stars with initial mass in the range 1.0M. to 1.6M.. In these models, contrary to what happens with the formulation of convective overshoot by Bressan et al. (1981) the central convection is not allowed to expand against gradients in molecular weight. We find that these models fit much better the overall morphology of the C-M diagram. This analysis is not possible for Be 42 due to the scarcely populated C-M diagram. Finally, we derive the luminosity function and present day mass function for the main sequence stars of the two clusters.
Database: 
WOK
Keywords: 
CLUSTERS-OPEN; STARS-C-M DIAGRAMS; STARS-STRUCTURE