Binary Planetary Nebula Central Stars: Validating Kepler/K2 Variability and Amplitudes

Jacoby, G. H.; Hillwig, T.; Crocker, A.; Dey, J.; Jones, D.; Tonry, J.; De Marco, O.
Bibliographical reference

American Astronomical Society Meeting Abstracts

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1
2020
Number of authors
7
IAC number of authors
1
Citations
0
Refereed citations
0
Description
We analyzed the Kepler/K2 Campaign 11 data to validate the periods and amplitudes for the 32 apparently variable central stars of planetary nebulae (PNe) in the sample of 140 PNe in the field. The K2 data yield good values for the periods, but the amplitudes are always too low by up to 10X due to dilution of the photometry from both the nebula and nearby stars in this crowded bulge field. Furthermore, the crowding forces the question of whether it is the PN central star that is varying or an unrelated nearby star in projection. We have investigated these issues using ground-based data from PanSTARRS, ATLAS, Las Campanas, CTIO, KPNO, and OGLE. In some cases, we are able to refine the amplitude measurements very significantly, allowing us to better define the parameters of the binary star systems. This work was supported in part by NASA grant NNX17AF80G.