2005/02/24 by L. Di Fabrizio, A. Bragaglia, M. Tosi +1
Physics and Astronomy · #Astronomy and Astrophysical Research #Galaxies: Formation, Evolution, Phenomena #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1111/j.1365-2966.2005.08963.x
published as Mon.Not.Roy.Astron.Soc. 359 (2005) 966-974 · Accepted for publication on MNRAS
arxiv created 2005/02/24 · openalex publication_date 2005/05/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We present deep CCD BVI photometry of the distant, old open cluster Berkeley 22, covering from the red giant branch (RGB) to about six magnitudes below the main-sequence (MS) turn-off. Using the synthetic colour–magnitude diagram method with three different types of stellar evolutionary tracks, we estimate values and theoretical uncertainties of the distance modulus (m−M)0, reddening E(B−V), age τ and approximate metallicity. The best fit to the data is obtained for 13.8 ≤ (m−M)0≤ 14.1, 0.64 ≤E(B−V) ≤ 0.65, 2.0 ≤τ≤ 2.5 Gyr (depending on the amount of overshooting from convective regions adopted in the stellar models) and solar metallicity.