Variability of Planetary Nebula Central Stars
Variability of Planetary Nebula Central Stars
For the past decade, we have been searching for short
timescale variability in the central stars of Galactic planetary nebulae (PNN).
By using CCDs to simultaneously measure the PNN and several comparison stars,
and by applying image analysis techniques to suppress or remove the background,
we have been able to derive relative magnitudes for the central stars with
an accuracy of ~0.004 mag, even through moonlight, bright nebulae, and 2
magnitudes worth of clouds. The purpose of this program is to find and
analyze close binary central stars, which are the remnants of
common-envelope evolution, non-radially pulsating central stars,
which can be studied via asteroseismology, and semi-regular
central stars, whose variability mechanism is unknown.
For further information see
- A
Schematic of the amplitude spectra of all known pulsating PNN and
GW Vir pulsating white dwarfs.
-
Publications based on monitoring program.
Web page by Robin Ciardullo ( rbc@astro.psu.edu )
Department of Astronomy and Astrophysics
Penn State University
