NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2018-10-22 T23:54:45 PDT
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For refcode 2007A&A...469L..31C:
Retrieve 21 NED objects in this reference.
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NED Abstract

Copyright by European Southern Observatory (ESO). Reproduced by permission
2007A&A...469L..31C On the optical counterpart of NGC 300 X-1 and the global Wolf-Rayet content of NGC 300 Crowther, P. A.; Carpano, S.; Hadfield, L. J.; Pollock, A. M. T. Abstract. Context: Surveys of Wolf-Rayet (WR) populations in nearby galaxies provide tests of evolutionary models plus type Ib/c supernova progenitors. This spectroscopic study complements the recent imaging survey of the spiral galaxy NGC 300 by Schild et al. Aims: Revisions to the known WR content of NGC 300 are presented. We investigate the WR nature of candidate #41 from Schild et al. which is spatially coincident with the bright X-ray point source NGC 300 X-1. Methods: VLT/FORS2 multi-object spectroscopy of WR candidates in NGC 300 is obtained. Results: We establish an early-type WN nature of #41, i.e. similar to the optical counterpart of IC 10 X-1, which closely resembles NGC 300 X-1. We confirm 9 new WR stars, bringing the current WR census of the inner disk to 31, with N(WC)/N(WN) ~ 0.9. Conclusions: If #41 is the optical counterpart for NGC 300 X-1, we estimate a WR mass of 38 M_o_ based upon ground-based photometry, from which a black hole mass of >=10 M_o_ results from the 32.8 h period of the system and WR wind velocity of 1250 km s^-1^. We estimate an 95% completeness among WC stars and 70% among WN stars, such that the total WR content is ~40, with N(WC)/N(WN) ~ 0.7. From the H{alpha}-derived star formation rate of the inner galaxy, we infer N(WR)/N(O) ~ 0.04. Key words: galaxies: individual: NGC 300, stars: Wolf-Rayet, X-rays: binaries, X-rays: individuals: NGC 300 X-1
Retrieve 21 NED objects in this reference.
Please click here for ADS abstract

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