The X-shooter Spectral Library and Carbon stars

Until recently, most empirical stellar spectral libraries were limited to a certain wavelength range or combined data from different stars, taken by different instruments of which some have low spectral resolution, limiting for instance our ability to analyze galaxies jointly in the ultraviolet, the optical and the near-infrared. The X-shooter Spectral Library, XSL, obtained using the X-shooter three-arm spectrograph on ESO's VLT, will help solving the current limitations. Here, we focus on spectra of carbon stars, which are part of this library. Carbon stars contribute significantly to the integrated spectra of galaxies containing young and intermediate-age populations, especially in the near-infrared, and therefore should be properly taken into account in stellar population synthesis models. A comparison with theoretical spectra is necessary to estimate the fundamental parameters of the observed stars, as well as to validate the spectral models across the broad ultraviolet to near-infrared wavelength range of X-shooter. We present preliminary results of such comparisons