6 papers · 1 filter
Models for WR and O Star Populations in Starbursts: New Developments and Applications to Large Samples of WR Galaxies
Daniel Schaerer
We summarise recent developments on synthesis models for massive star populations with a particular emphasis on Wolf-Rayet (WR) stars. Quantitative analysis of the stellar content…
New light on the origin of nebular HeII emission in young starbursts
Daniel Schaerer
We review the observations of nebular HeII 4686 emission in Local Group objects and extra-galactic HII regions. Different ionization mechanisms proposed to explain the unusually hi…
The impact of new ionizing fluxes on ISO observations of HII regions and starbursts
Daniel Schaerer, Grazyna Stasinska
Extensive grids of photoionization models have been calculated for single star HII regions and evolving starbursts. We illustrate the predictions for IR fine structure lines which…
Populations of WC and WN stars in Wolf-Rayet galaxies
Daniel Schaerer, Thierry Contini, Daniel Kunth
We report the detection of WC stars in 5 Wolf-Rayet (WR) galaxies: He 2-10, NGC 3049, NGC 3125, NGC 5253 and Tol 89. The faint broad CIV5808 line requires sufficiently high S/N to…
Massive star populations in I Zw 18: A probe of stellar evolution in the early universe
Daniel Schaerer, Duilia de Mello, Claus Leitherer +1
We present a study of the gaseous and stellar emission in I Zw18, the most metal-poor star-forming galaxy known. Archival HST WFPC2 and FOS data have been used to analyze the spati…
On some properties of very metal-rich stars
N. Mowlavi, G. Meynet, A. Maeder +2
An analysis of some properties of stellar models as a function of metallicity Z (and helium content Y) is presented, with special attention to those stars with metallicities higher…