A grid of synthetic spectra and indices
Fe5270, Fe5335, Mgb and Mg
as a function of stellar parameters and
[ 
/Fe]
*,**
1
Universidade de São Paulo, Rua do Matão 1226, São Paulo 05508-900, Brazil e-mail: pcoelho@usp.br
2
Observatoire de Paris, 61 av. de l'Observatoire, 75014 Paris, France e-mail: Marie-Noel.Perrin@obspm.fr,Roger.Cayrel@obspm.fr
3
Observatoire de Paris-Meudon, 92195 Meudon, France e-mail: David.Katz@obspm.fr,Monique.Spite@obspm.fr,Claude.Vantveer@obspm.fr
Corresponding author: B. Barbuy, barbuy@astro.iag.usp.br
Received:
30
August
2000
Accepted:
20
March
2003
We have computed a grid of synthetic spectra in the
wavelength range 
4600–5600 Å
using revised model atmospheres,
for a range of atmospheric parameters and
values of [ 
and +0.4.
The Lick indices Fe5270, Fe5335, Mgb and Mg2 are measured
on the grid spectra for 
to 8.3 Å.
Relations between the indices Fe5270, Fe5335 and Mg2
and the stellar parameters
effective temperature 
, [Fe/H] and
[ α/Fe] , valid in the range 
K, are presented. These
fitting functions are given for 
and 8.3 Å.
The indices were also
measured for a list of 97 reference stars with
well-known stellar parameters observed at ESO and OHP, and these
are compared to the computed indices.
Finally,
a comparison of the indices measured on the observed spectra
and those derived from
the fitting functions based on synthetic spectra is presented.
Key words: stars: abundances
© ESO, 2003