A spectroscopic study of the Open Cluster NGC 6475 (M 7) Chemical
  Abundances from stars in the range T = 4500-10000 K
  Clusters of stars are key objects for the study of the dynamical and chemical
evolution of the Galaxy and its neighbors. In particular chemical composition
is obtained from different kinds of stars (hot main-sequence stars, cool
main-sequence stars, horizontal-branch stars, RGB stars) using different
methodologies. Our aim is to apply these methodologies to the stars of the Open
Cluster NGC 6475. Obtaining a census of the most important elements we will be
able to test their consistence. We finally want to establish more robust
fundamental parameters for this cluster.We selected high S/N high resolution
spectra of 7 stars of the Open Cluster NGC 6475 from the ESO database covering
the T$_{\rm eff}$ range 4500-10000 K and of luminosity class V (dwarf) and III
(giants). We determined the chemical abundances of several elements. For hot
stars (T$_{\rm eff}$$>$9000 K) we applied the Balmer Lines fitting method to
obtained atmospheric parameters. For cool stars (T$_{\rm eff}$$<$6500 K) we
used the FeI/II abundance equilibrium method. For the two groups of stars the
use of different line-lists was mandatory. LTE approximation was used. For
elements affected by NLTE deviation (C,N,O,Na,Mg) corrections were applied. The
abundance of many elements were obtained from the measurement of the equivalent
width of spectral lines. For those elements for which only blended lines were
available (O, He) comparison of real spectrum with synthetic ones was used.
Hyperfine structure was taken in account for V and Ba.
