New Wolf‐Rayet Galaxies with Detection of WC Stars

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Abstract
We report the discovery of two new Wolf-Rayet (W-R) galaxies: Mrk 1039 and F08208+2816. Two broad W-R bumps at 5808 and 4650 Å indicate the presence of early-type WC (WCE) and late-type WN (WNL) star populations in both sources. We also confirm the presence of W-R features in Mrk 35, previously detected in a different position. The observed equivalent width of the W-R bump at 4650 Å and the derived number ratios of W-R/(W-R+O) imply that star formation in these sources takes place in short burst durations. Comparisons with the recent models of W-R populations in young starbursts with the observed EW(He II λ4686), EW(C IV λ5808), and EW(W-R bump) and their relative intensities provide an indication that the stellar initial mass function in some W-R galaxies might not be Salpeter-like. It is interesting to find that the luminous IRAS source F08208+2816 has little dust reddening, probably because of the existence of a powerful superwind. By comparisons with other starbursts observed with the Hopkins Ultraviolet Telescope, F08208+2816 as a merging system renders a chance to study the contribution from young starbursts to the UV background radiation in the universe.
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