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Title: BINARY CENTRAL STARS OF PLANETARY NEBULAE DISCOVERED THROUGH PHOTOMETRIC VARIABILITY. IV. THE CENTRAL STARS OF HaTr 4 AND Hf 2-2

Journal Article · · Astronomical Journal (Online)
;  [1];  [2];  [3];  [4]
  1. Department of Physics and Astronomy, Valparaiso University, Valparaiso, IN 46383 (United States)
  2. Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States)
  3. Department of Physics, The University of Hong Kong, Pokfulam Road (Hong Kong)
  4. Southeastern Association for Research in Astronomy (SARA) (United States)

We explore the photometrically variable central stars of the planetary nebulae HaTr 4 and Hf 2-2. Both have been classified as close binary star systems previously based on their light curves alone. Here, we present additional arguments and data confirming the identification of both as close binaries with an irradiated cool companion to the hot central star. We include updated light curves, orbital periods, and preliminary binary modeling for both systems. We also identify for the first time the central star of HaTr 4 as an eclipsing binary. Neither system has been well studied in the past, but we utilize the small amount of existing data to limit possible binary parameters, including system inclination. These parameters are then compared to nebular parameters to further our knowledge of the relationship between binary central stars of planetary nebulae and nebular shaping and ejection.

OSTI ID:
22662993
Journal Information:
Astronomical Journal (Online), Vol. 152, Issue 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 1538-3881
Country of Publication:
United States
Language:
English