Synthetic High‐Resolution Line Spectra of Star‐forming Galaxies below 1200 A

We have generated a set of far-ultraviolet stellar libraries using spectra ofOB and Wolf-Rayet stars in the Galaxy and the Large and Small Magellanic Cloud.The spectra were collected with the Far Ultraviolet Spectroscopic Explorer andcover a wavelength range from 1003.1 to 1182.7A at a resolution of 0.127A. Thelibraries extend from the earliest O- to late-O and early-B stars for theMagellanic Cloud and Galactic libraries, respectively. Attention is paid to thecomplex blending of stellar and interstellar lines, which can be significant,especially in models using Galactic stars. The most severe contamination is dueto molecular hydrogen. Using a simple model for the H$_2$ line strength, wewere able to remove the molecular hydrogen lines in a subset of MagellanicCloud stars. Variations of the photospheric and wind features of CIII 1176, OVI1032, 1038, PV 1118, 1128, and SIV 1063, 1073, 1074 are discussed as a functionof temperature and luminosity class. The spectral libraries were implementedinto the LavalSB and Starburst99 packages and used to compute a standard set ofsynthetic spectra of star-forming galaxies. Representative spectra arepresented for various initial mass functions and star formation histories. Thevalid parameter space is confined to the youngest ages of less than 10 Myr foran instantaneous burst, prior to the age when incompleteness of spectral typesin the libraries sets in. For a continuous burst at solar metallicity, theparameter space is not limited. The suite of models is useful for interpretingthe restframe far-ultraviolet in local and high-redshift galaxies.Comment: 33 pages including 13 figures, accepted for publication in Ap