Self-consistent physical parameters for five intermediate-age SMC
  stellar clusters from CMD modelling
  Context. Stellar clusters in the Small Magellanic Cloud (SMC) are useful
probes for studying the chemical and dynamical evolution of this neighbouring
dwarf galaxy, enabling inspection of a large period covering over 10 Gyr. Aims:
The main goals of this work are the derivation of age, metallicity, distance
modulus, reddening, core radius, and central density profiles for six sample
clusters, in order to place them in the context of the Small Cloud evolution.
The studied clusters are AM 3, HW 1, HW 34, HW 40, Lindsay 2, and Lindsay 3; HW
1, HW 34, and Lindsay 2 are studied for the first time. Methods: Optical
colour-magnitude diagrams (V,B - V CMDs) and radial density profiles were built
from images obtained with the 4.1 m Southern Astrophysical Research (SOAR)
telescope, reaching V ~ 23. The determination of structural parameters were
carried out by applying King profile fitting. The other parameters were derived
in a self-consistent way by means of isochrone fitting, which uses likelihood
statistics to identify the synthetic CMDs that best reproduce the observed
ones. Membership probabilities were determined comparing the cluster and
control field CMDs. Completeness and photometric uncertainties were obtained by
performing artificial star tests. Results: The results confirm that these
clusters (except HW 34, identified as a field fluctuation) are intermediate-age
clusters, with ages between 1.2 Gyr (Lindsay 3) and ~5.0 Gyr (HW 1). In
particular HW 1, Lindsay 2 and Lindsay 3 are located in a region that we called
West Halo, where studies of ages and metallicity gradients are still lacking.
Moreover, Lindsay 2 was identified as a moderately metal-poor cluster with
[Fe/H] = -1.4 +/- 0.2 dex, lower than expected from the age-metallicity
relation by Pagel & Tautvaisiene (1998). We also found distances varying from
~53 kpc to 66 kpc, compatible with the large depth of the SMC.
