Other
Scientific paper
Apr 1998
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1998apj...497..896m&link_type=abstract
Astrophysical Journal v.497, p.896
Other
44
Stars: Binaries: Eclipsing, Stars: Individual Henry Draper Number: Hd 5980, Stars: Mass Loss, Stars: Variables: Other, Stars: Wolf-Rayet
Scientific paper
The 1994 LBV-(luminous blue variable)like outburst of one of the luminous, hot components of the binary HD 5980 made it the brightest star in the Small Magellanic Cloud for an interval of 5 months. The most intriguing question to arise from this event is the following: Why did the HD 5980 spectrum change from an H-poor WN3 with veiled OB absorption lines about 20 yr ago to an H-rich WN11 without central absorption lines during the outburst? In an attempt to answer this apparent enigma, we present and analyze new phase-dependent spectroscopic, polarimetric, and light-curve observations. Together with other published data, these new observations allow us to improve the orbital parameters considerably, except for the radial velocity amplitudes and hence the masses, which are only roughly constrained. Especially important in HD 5980 is the strong collision of the two nearly equal pre-outburst winds. The emission-line spectrum generated by the collision tends to mask the underlying line spectra of both components when the system is relatively quiescent. We argue that the pre-erupting system consists of a very luminous but moderately massive H-rich O type supergiant, possibly with emission lines, and a low-mass, H-poor, relatively faint WN companion, whose lines are mostly drowned out by wind collision emission, the spectrum of which largely imitates that of a WNE star. It was the O supergiant that erupted in a normal way as an H-rich, visually bright WN11 star. In this way, the need for peculiar evolutionary scenarios (e.g., rapid evolution from a faint, low-mass, H-poor WNE star to a luminous, H-rich WNL star) is avoided.
Balona Luis
Bartzakos Peter
Cerruti Miguel Angel
Lamontagne Robert
Magalhaes Antonio Mario
No associations
LandOfFree
The Luminous Eclipsing SMC OB + WN Binary HD 5980 before and during the Recent LBV-like Outburst: an Extreme Case of Colliding Winds does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The Luminous Eclipsing SMC OB + WN Binary HD 5980 before and during the Recent LBV-like Outburst: an Extreme Case of Colliding Winds, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Luminous Eclipsing SMC OB + WN Binary HD 5980 before and during the Recent LBV-like Outburst: an Extreme Case of Colliding Winds will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1602754