XSL simple stellar population models based on the empirical X-shooter Spectral Library from near-ultraviolet to near-infrared (NIR) wavelengths. The models span the metallicity range −2.2 < [Fe/H] < +0.2 and
ages above 50 Myr. The unmatched characteristics of relatively high resolution and extended wavelength coverage (350–2480 nm, R ∼ 10 000) of the XSL population models bring us closer to bridging optical and NIR studies of intermediate and old stellar populations. See Verro et al. (2022b) for more details.
Examples of XSL PARSEC/COLIBRI Salpeter SSP models.