1994A&A...285..943C

We develop a general method which allows us to derive fundamental stellar parameters (T_eff, [M/H]) of F, G, and K dwarfs from low-resolution spectra covering the wavelength range 370-780 nm and using three different grids of model atmosphere flux distributions. Two extreme cases are explored: (1) broad-band synthetic color indices, which exploit a large fraction of the available wavelength range, but at highly degraded spectral resolution, and (2) synthetic spectrum fitting, which takes full advantage of the available resolution in the data, but which is limited to a relatively narrow wavelength interval. We show that, while in either case the initial model-derived parameter values differ systematically from published results obtained via high-resolution spectroscopy these spectroscopic data can be used to properly calibrate the models. Thus, as an application, we were able to derive abundances for 40 proper motion stars, selected from Fresneau (1990). Within the systematic biases that could exist, the derived metallicity distribution is bimodal, one mode centered on [M/H] = 0.0dex (thin disk) and the other on [M/H] = -0.6dex (thick disk), biased towards the thick disk. Furthermore, three low metallicity stars and a super metal-rich one have been discovered.