A library of high resolution synthetic stellar spectra from 300 nm to 1.8 ${\rm \mu}$m with solar andα-enhanced composition

Abstract

Libraries of stellar spectra are fundamental tools for the study of stellar populations, and both empirical and synthetic libraries have been used for this purpose. In this paper, a new library of high resolution synthetic spectra is presented, ranging from the near-ultraviolet (300 nm) to the near-infrared (1.8 µm). The library spans all the stellar types that are relevant to the integrated light of old and intermediate-age stellar populations in the involved spectral region (spectral types F through M and all luminosity classes). The grid was computed for metallicities ranging from [Fe/H] = -2.5 to +0.5, including both solar and α-enhanced ([α/Fe] = 0.4) chemical compositions. The synthetic spectra are a good match to observations of stars throughout the stellar parameter space encompassed by the library and over the whole spectral region covered by the computations.

Evolutionary stellar population synthesis with MILES – II. Scaled-solar and α-enhanced models

“…other Fe-sensitive indices, as a result of its sensitivity to Ti abundance, which is enhanced in the α-enhanced models Johansson et al 2012). The same applies to Fe 4531 for which we also see that the α-enhanced model lines are closer to the corresponding base model lines (see also figure 9 in ) This beahviour is also seen for fixed [Fe/H], as Mg, i.e an important electron donor, tends to lower the true continuum (Barbuy et al 2003;Coelho et al 2005).…”

“…The Coelho et al (2005) theoretical library covers effective temperatures, T eff , between 3500 and 7000 K, surface gravities, log g, between +0.0 and +5.0, iron metallicities, [Fe/H] The accuracy of this library has been assessed in Martins & Coelho (2007), who showed that this library had the highest success in reproducing spectral features of observed stars among the theoretical libraries analysed in that work. The spectra have higher spectral resolution and wavelength coverage than MILES, therefore they were convolved with a gaussian kernel and were resampled to match MILES spectral resolution, dispersion and wavelength coverage.…”

“…For this purpose we apply a differential correction to our empirical SSP models which is obtained from the theoretical stellar spectral library of Coelho et al (2005Coelho et al ( , 2007. We also employ the scaled-solar and α-enhanced isochrones of BaSTI (Pietrinferni et al , 2006.…”

Tracing the evolution of the Galactic bulge with chemodynamical modelling of alpha-elements

“…The spectrum synthesis code used is described in Barbuy et al (2003) and Coelho et al (2005). The stellar parameters reported in Table A.1 were adopted from the detailed analyses by Zoccali et al (2006) and Lecureur et al (2007) for 43 bulge field red giants.…”

Population Synthesis at Short Wavelengths and Spectrophotometric Diagnostic Tools for Galaxy Evolution

“…for λ < ∼ 3000Å) we can presently count on important theoretical datasets covering the full parameter space to reproduce stellar spectral energy distribution (SED) across the whole H-R diagram, at wavelength resolution typically better than λ/∆λ > ∼ 20 000 (see Bertone, 2005, for an exhaustive review on this subject). Among others, these include the work of Rodríguez-Merino et al (2005) (Uvblue spectral library), Gustafsson et al (2003) (Marcs model grid), Munari et al (2005), Hauschildt et al (1999) (the NextGen library), and Coelho et al (2005).…”