Characterization of NGC6705 (M11) open cluster

Abstract

The main purpose of this work is to derive the physical properties of NGC6705 open cluster using Strömgren photometry; such as distance, average colour excess, metallicity and age. Besides, this method provides individual temperatures, gravities and metallicities that are compared to the spectroscopic independent results from Gaia-ESO survey. 12137 stars with all Strömgren indices are obtained out of 63437 stars that have partial data on m1, c1 and H[beta] indices, with V reaching a limiting magnitude of [infinit]21m. The physical parameters obtained from an automatic algorithm lead to the evidence of differential reddening with a mean value of E(b-y) = 0m:30+-0m:02, metallicity of [Fe=H] = -0:3 +- 0:3 dex and absolute distance modulus of V0 - MV = 12m:0 +- 0m:3. From PARSEC and Dartmouth isochrones' best fit, we retrieve that NGC6705 is a 250-316 Myr open cluster that has a turn off mass of 3:3 +- 0:2M, E(b - y) = 0m:30 +- 0m:01, V0 - MV = 11m:5 +- 0m:1 and [Fe=H] = -0:1 +- 0:1 dex.