Analytical Studies of NGC 2571, NGC 6802, Koposov 53 and Be 89
  Astrophysical parameters (age, reddening, distance, radius, luminosity function, mass function, total mass, relaxation time and mass segregation) have been estimated for open clusters NGC 2571, NGC 6802, Koposov 53 and Be 89 by using the Two Micron All Sky Survey (2MASS) photometry. We analyse the color-magnitude diagrams and stellar radial density profiles. We have found that NGC 2571 is the youngest one having young main sequence stars while Be 89 is the oldest cluster. 
Ferhat F. \"Ozeren, \"Ozg\"un Arslan, \.Ibrahim K\"u\c{c}\"uk, \.Inci   Akkaya Oralhan
astro-ph.GA