Medium resolution INT Library of Empirical Spectra

A new stellar library developed for stellar population synt hesis modeling is presented. The li- brary consist of 985 stars spanning a large range in atmospheric parameters. The spectra were obtained at the 2.5m INT telescope and cover the range λλ 3525-7500 ˚ A at 2.3 ˚ A (FWHM) spectral resolution. The spectral resolution, spectral ty pe coverage, flux calibration accuracy and number of stars represent a substantial improvement over previous libraries used in pop- ulation synthesis models.