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The spectral predictions of stellar population models are not as accurate in the ultra-violet (UV) as in the optical wavelength domain. One of the reasons is the lack of high-quality stellar libraries. The New Generation Stellar Library (NGSL), recently released,represents a significant step towards the improvement of this situation. To prepare NGSL for population synthesis, we determined the atmospheric parameters of its stars, we assessed the precision of the wavelength calibration and characterised its intrinsic resolution. We also measured the Galactic extinction for each of the NGSL stars. For our analyses we used ULySS, a full spectrum fitting package, fitting the NGSL spectra against the MILES interpolator. We find that the wavelength calibration is precise up to 0.1 px, after correcting a systematic effect in the optical range. The spectral resolution varies from 3{AA} in the UV to 10{AA} in the near-infrared (NIR), corresponding to a roughly constant reciprocal resolution R ~ 1000 and an instrumental velocity dispersion $sigma_{ins}$ ~ 130 km/s. We derived the atmospheric parameters homogeneously. The precision for the FGK stars is 42K, 0.24 and 0.09 dex for Teff, logg and [Fe/H], respectively. The corresponding mean errors are 29K, 0.50 and 0.48 dex for theMstars, and for the OBA stars they are 4.5 percent, 0.44 and 0.18 dex. The comparison with the literature shows that our results are not biased.
(Aims) We present a number of improvements to the MILES library and stellar population models. We correct some small errors in the radial velocities of the stars, measure the spectral resolution of the library and models more accurately, and give a b
We use the first release of the SDSS/MaStar stellar library comprising ~9000, high S/N spectra, to calculate integrated spectra of stellar population models. The models extend over the wavelength range 0.36-1.03 micron and share the same spectral res
[Abridged]. We present SEDs for single-age, single-metallicity stellar populations (SSPs) covering the optical range at resolution 2.3A (FWHM). These SEDs constitute our base models, as they combine scaled-solar isochrones with MILES empirical stella
We present the first single-burst stellar population models in the infrared wavelength range between 2.5 and 5 {mu}m which are exclusively based on empirical stellar spectra. Our models take as input 180 spectra from the stellar IRTF (Infrared Telesc
MEGARA (Multi Espectr{o}grafo en GTC de Alta Resoluci{o}n para Astronom{i}a) is an optical (3650~--~9750AA), fibre-fed, medium-high spectral resolution (R = 6000, 12000, 20000) instrument for the GTC 10.4m telescope, commissioned in the summer of 201