@article{HillwigReindlRotteretal.2022,
  author    = {Hillwig, Todd C. and Reindl, Nicole and Rotter, Hannah M. and Rengstorf, Adam W. and Heber, Ulrich and Irrgang, Andreas},
  title     = {Two evolved close binary stars: GALEX J015054.4+310745 and the central star of the planetary nebula Hen 2-84},
  series = {Monthly notices of the Royal Astronomical Society},
  volume    = {511},
  journal   = {Monthly notices of the Royal Astronomical Society},
  number    = {2},
  publisher = {Oxford Univ. Press},
  address   = {Oxford},
  issn      = {0035-8711},
  doi       = {10.1093/mnras/stac226},
  pages     = {2033 -- 2039},
  year      = {2022},
  abstract  = {As part of a survey to find close binary systems among central stars of planetary nebula, we present two newly discovered binary systems. GALEX J015054.4+310745 is identified as the central star of the possible planetary nebula Fr 2-22. We find it to be a single-lined spectroscopic binary with an orbital period of 0.2554435(10) d. We support the previous identification of GALEX J015054.4+310745 as an sdB star and provide physical parameters for the star from spectral modelling. We identify its undetected companion as a likely He white dwarf. Based on this information, we find it unlikely that Fr 2-22 is a true planetary nebula. In addition, the central star of the true planetary nebula Hen 2-84 is found to be a photometric variable, likely due to the irradiation of a cool companion. The system has an orbital period of 0.485645(30) d. We discuss limits on binary parameters based on the available light-curve data. Hen 2-84 is a strongly shaped bipolar planetary nebula, which we now add to the growing list of axially or point-symmetric planetary nebulae with a close binary central star.},
  language  = {en}
}