SPADES: a Stellar PArameters DEtermination Software

TL;DR

SPADES is an automated software tool designed to determine stellar parameters such as temperature, gravity, and metallicity from spectroscopic data, suitable for large surveys like Gaia.

Contribution

It introduces an automatic, line-by-line spectral comparison method for stellar parameter determination applicable to all star types, building on previous software experiences.

Findings

Effective with high-resolution spectra (R=25000)

Performs well at various signal-to-noise ratios, down to 30

Simulates spectra similar to Gaia-ESO Survey data

Abstract

With the large amounts of spectroscopic data available today and the very large surveys to come (e.g. Gaia), the need for automatic data analysis software is unquestionable. We thus developed an automatic spectra analysis program for the determination of stellar parameters: radial velocity, effective temperature, surface gravity, micro-turbulence, metallicity and the elemental abundances of the elements present in the spectral range. Target stars for this software should include all types of stars. The analysis method relies on a line by line comparison of the spectrum of a target star to a library of synthetic spectra. The idea is built on the experience acquired in developing the TGMET (Katz et al. 1998 and Soubiran et al. 2003) ETOILE (Katz 2001) and Abbo (Bonifacio & Caffau 2003) softwares. The method is presented and the performances are illustrated with GIRAFFE-like simulated spectra with high resolution (R = 25000), with high and low signal to noise ratios (down to SNR= 30). These spectra should be close to what could be targeted by the Gaia-ESO Survey (GCDS).