%0 Generic %1 vidalgarcia2017modelling %A Vidal-García, A. %A Charlot, S. %A Bruzual, G. %A Hubeny, I. %D 2017 %K ISM UV diagnostics line stars %R 10.1093/mnras/stx1324 %T Modelling ultraviolet-line diagnostics of stars, the ionized and the neutral interstellar medium in star-forming galaxies %U http://arxiv.org/abs/1705.10320 %X We combine state-of-the-art models for the production of stellar radiation and its transfer through the interstellar medium (ISM) to investigate ultraviolet-line diagnostics of stars, the ionized and the neutral ISM in star-forming galaxies. We start by assessing the reliability of our stellar population synthesis modelling by fitting absorption-line indices in the ISM-free ultraviolet spectra of 10 Large-Magellanic-Cloud clusters. In doing so, we find that neglecting stochastic sampling of the stellar initial mass function in these young ($\sim10$-100 Myr), low-mass clusters affects negligibly ultraviolet-based age and metallicity estimates but can lead to significant overestimates of stellar mass. Then, we proceed and develop a simple approach, based on an idealized description of the main features of the ISM, to compute in a physically consistent way the combined influence of nebular emission and interstellar absorption on ultraviolet spectra of star-forming galaxies. Our model accounts for the transfer of radiation through the ionized interiors and outer neutral envelopes of short-lived stellar birth clouds, as well as for radiative transfer through a diffuse intercloud medium. We use this approach to explore the entangled signatures of stars, the ionized and the neutral ISM in ultraviolet spectra of star-forming galaxies. We find that, aside from a few notable exceptions, most standard ultraviolet indices defined in the spectra of ISM-free stellar populations are prone to significant contamination by the ISM, which increases with metallicity. We also identify several nebular-emission and interstellar-absorption features, which stand out as particularly clean tracers of the different phases of the ISM.

@misc{vidalgarcia2017modelling, abstract = {We combine state-of-the-art models for the production of stellar radiation and its transfer through the interstellar medium (ISM) to investigate ultraviolet-line diagnostics of stars, the ionized and the neutral ISM in star-forming galaxies. We start by assessing the reliability of our stellar population synthesis modelling by fitting absorption-line indices in the ISM-free ultraviolet spectra of 10 Large-Magellanic-Cloud clusters. In doing so, we find that neglecting stochastic sampling of the stellar initial mass function in these young ($\sim10$-100 Myr), low-mass clusters affects negligibly ultraviolet-based age and metallicity estimates but can lead to significant overestimates of stellar mass. Then, we proceed and develop a simple approach, based on an idealized description of the main features of the ISM, to compute in a physically consistent way the combined influence of nebular emission and interstellar absorption on ultraviolet spectra of star-forming galaxies. Our model accounts for the transfer of radiation through the ionized interiors and outer neutral envelopes of short-lived stellar birth clouds, as well as for radiative transfer through a diffuse intercloud medium. We use this approach to explore the entangled signatures of stars, the ionized and the neutral ISM in ultraviolet spectra of star-forming galaxies. We find that, aside from a few notable exceptions, most standard ultraviolet indices defined in the spectra of ISM-free stellar populations are prone to significant contamination by the ISM, which increases with metallicity. We also identify several nebular-emission and interstellar-absorption features, which stand out as particularly clean tracers of the different phases of the ISM.}, added-at = {2017-05-31T09:48:01.000+0200}, author = {Vidal-García, A. and Charlot, S. and Bruzual, G. and Hubeny, I.}, biburl = {https://www.bibsonomy.org/bibtex/21e0c4a78e21f53746685213c42087b28/miki}, description = {[1705.10320] Modelling ultraviolet-line diagnostics of stars, the ionized and the neutral interstellar medium in star-forming galaxies}, doi = {10.1093/mnras/stx1324}, interhash = {9f9d2d9312755173969da4ad3458de26}, intrahash = {1e0c4a78e21f53746685213c42087b28}, keywords = {ISM UV diagnostics line stars}, note = {cite arxiv:1705.10320Comment: 27 pages, 21 figures. Accepted for publication in MNRAS}, timestamp = {2017-05-31T09:48:01.000+0200}, title = {Modelling ultraviolet-line diagnostics of stars, the ionized and the neutral interstellar medium in star-forming galaxies}, url = {http://arxiv.org/abs/1705.10320}, year = 2017 }