Astronomy and Astrophysics – Astrophysics
Scientific paper
2008-05-06
Astronomy and Astrophysics
Astrophysics
6 pages, 4 figures, to be published in the Proceedings of Massive Stars as Cosmic Engines, IAU Symp 250, ed. F. Bresolin, P. A
Scientific paper
10.1017/S174392130802036X
Luminous blue variables (LBVs) are characterized by semi-periodic episodes of enhanced mass-loss, or outburst. The cause of these outbursts has thus far been a mystery. One explanation is that they are initiated by kappa-effect pulsations in the atmosphere caused by an increase in luminosity at temperatures near the so-called ``iron bump'' (T ~ 200,000 K), where the Fe opacity suddenly increases. Due to a lag in the onset of convection, this luminosity can build until it exceeds the Eddington limit locally, seeding pulsations and possibly driving some mass from the star. We present some preliminary results from a parameter study focusing on the conditions necessary to trigger normal S-Dor type (as opposed to extreme eta-Car type) outbursts. We find that as Y increases or Z decreases, the pulsational amplitude decreases and outburst-like behavior, indicated by a large, sudden increase in photospheric velocity, becomes likes likely.
Guzik Joyce Ann
Onifer Andrew J.
No associations
LandOfFree
Pulsation-Initiated Mass Loss in Luminous Blue Variables: A Parameter Study 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 Pulsation-Initiated Mass Loss in Luminous Blue Variables: A Parameter Study, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Pulsation-Initiated Mass Loss in Luminous Blue Variables: A Parameter Study will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-209485