Binary Central Stars of Planetary Nebula |
BackgroundSingle star evolutionary channels are still thought to be at the root of the evolution of most Planetary Nebulae (PNe). Despite the fact that most PNe are not circular, binary channels have been thought to be of secondary importance, mostly due to the fact that only a handful of binary central stars of PN have ever been found. Recent theoretical work has however convinced a sizable amount of PN astronomers that binarity might play a much more important role in the formation and shaping of PNe than previously acknowledged. At this root of this shift is a corpus og observational and theoretical work that I have participated in.My ProjectsSearching for binary stars in PN is at the root of my observational work. We have been searcing, and finding binaries, both using photometric technqies and radial velocity techniques. Photometrically the simplest way to find binaries is by variability, something that finds only close binaries (usually post-common envelope binaires). This work has been headed by Todd Hillwig (Valparaiso University). IR excess can also be used to find companions with arbitrary separation, but typical companions would be at the detection limits. Radial velocty has limitation with separations much larger than a few solar radii, but it has met with some success (these projected are headed by David Jones at the IAC and Hans Van Winkel at KU Leuven). I have also been working on population synthesis, though it has been a while. The first paper was well received, while the second is still in draft after 10 years.PublicatonsDe Marco, O., Hillwig, T., Smith, A.J., 2008 , as well as Papers II to IV in the same series accessible through the link.
De Marco, O., Wortel, S., Bond, H.E., Harmer, D., 2008, Asymmetric PN IV
De Marco, O., Bond, H.E., Harmer, D., & Fleming, A.F., 2004, ApJ Letters 602, 93
Moe, M., & De Marco, O., 2006, ApJ 650, 916 |
Last Update: March 2018