相关论文: New Wolf-Rayet Galaxies with Detection of WC Stars
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 be detected explaining the non-detection of this WC feature…
Wolf-Rayet stars (WR) have been detected in the NW region of the metal-poor starburst galaxy IZw 18. The integrated luminosity and FWHM of the bumps at 4650 A and 5808 A are consistent with the presence of a few individual stars of WC4 or…
(Abridged) We perform a comprehensive multiwavelength analysis of a sample of 20 starburst galaxies that show the presence of a substantial population of Wolf-Rayet (WR) stars. In this paper we present the analysis of the O and WR star…
We analyze long-slit spectral observations of 39 Wolf-Rayet (WR) galaxies with heavy element mass fraction ranging over 2 orders of magnitude, from Zsun/50 to 2Zsun. Nearly all galaxies in our sample show broad WR emission in the blue…
We analyze longslit spectral observations of fourteen Wolf-Rayet galaxies from the sample of Schaerer, Contini & Pindao (1999). All 14 galaxies show broad Wolf-Rayet emission in the blue region of the spectrum, consisting of a blend of…
Detection and analysis of Wolf-Rayet (WR) star populations in young starbursts is a powerful tool to reveal the properties of the star-forming events. We present new high S/N optical spectra of a sample of well-known WR galaxies, in which…
We report the discovery of emission from Wolf-Rayet stars in a giant HII region 4.5 arcsec South of the nucleus of the IRAS barred spiral galaxy Mrk 712. The ratio of WNL to OV stars, estimated from the luminosity of the HeII 4686 line, is…
We report the discovery of broad Wolf-Rayet emission lines in the Multiple Mirror Telescope (MMT) spectrum of the NW component of I Zw 18, the lowest-metallicity blue compact dwarf (BCD) galaxy known. Two broad Wolf-Rayet (W-R) bumps at the…
Wolf-Rayet (WR) galaxies provide detailed information on massive star populations in starbursts and thereby represent ideal objects to determine accurate ages for young systems, to measure the burst duration, and to probe the upper end of…
Wolf-Rayet stars (WRs) are evolved massive stars in the brief stage before they undergo core collapse. Not only are they rare, but they also can be particularly difficult to find due to the high extinction in the Galactic plane. This paper…
The discovery of new Wolf-Rayet (WR) stars in our Galaxy via large-scale narrowband optical surveys has been severely limited by dust extinction. Recent improvements in infrared technology have made narrowband-broadband imaging surveys…
Preliminary results from spectrophotometric observations of galaxies with very young starbursts are presented. Starburst galaxies with an age of the burst in the range between 3 and 6 Myr have been observed and new detections of Wolf-Rayet…
Determining the Galactic distribution and numbers of massive stars, such as Wolf-Rayet stars (WRs), is hampered by intervening Galactic or local circumstellar dust obscuration. In order to probe such regions of the Galaxy we can use…
We report the discovery of fifteen previously unknown Wolf-Rayet (WR) stars found as part of an infrared broad-band study of candidate WR stars in the Galaxy. We have derived an empirically-based selection algorithm which has selected ~5000…
We have spectroscopically identified 60 Galactic Wolf-Rayet (WR) stars, including 38 nitrogen types (WN) and 22 carbon types (WC). Using photometry from the Spitzer/GLIMPSE and 2MASS databases, the WRs were selected via a method we have…
We have carried out a search for Wolf-Rayet galaxies in all galaxies with EW(Hb)>2AA in the SDSS DR6. We identify Wolf-Rayet features using a mixture of automatic and visual classification and find a total of 570 galaxies with significant…
The total population of Wolf-Rayet (WR) stars in the Galaxy is predicted by models to be as many as $\sim$6000 stars, and yet the number of catalogued WR stars as a result of optical surveys was far lower than this ($\sim$200) at the turn…
We report new results from our effort to identify obscured Wolf-Rayet stars in the Galaxy. Candidates were selected by their near-infrared (2MASS) and mid-infrared (Spitzer/GLIMPSE) color excesses, which are consistent with free-free…
We present spectroscopic observations of the central star clusters in NGC 5253 the aim of which is to search for WC stars. Our observations show the presence of Wolf-Rayet (WR) stars not only of WN but also of WC subtype in two star forming…
We report the first-ever discovery of an extragalactic Wolf-Rayet (WR)star with Spitzer. A new WR star in the Large Magellanic Cloud (LMC) was revealed via detection of its circumstellar shell using 24 {\mu}m images obtained in the…