Hubble Space Telescope and Optical Observations of Three Pulsating Accreting White Dwarfs in Cataclysmic Variables
Szkody, Paula; Sion, Edward M.; Solheim, Jan-Erik; Gänsicke, Boris T.; Mukadam, Anjum; Henden, Arne; Nitta, Atsuko; Woudt, Patrick A.; Warner, Brian; Sahu, D. K.; Prabhu, T.
United States, United Kingdom, South Africa, Norway, India
Abstract
Ultraviolet observations using the Solar Blind Channel on the Hubble Space Telescope provide light curves and low-resolution spectra of three pulsating white dwarfs in the cataclysmic variables SDSS J013132.39-090122.3, SDSS J161033.64-010223.3, and SDSS J220553.98+115553.7. The UV light curves show enhanced pulsation amplitudes over those from simultaneous and previous optical photometry, while the UV-optical spectra are fit with white dwarf temperatures near 15,000 K. These temperatures place the accreting white dwarfs outside the instability zone for noninteracting DAV white dwarfs and show that the instability strip is complex for accreting white dwarfs.
Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555 with the Apache Point Observatory 3.5 m telescope, which is owned and operated by the Astrophysical Research Consortium; and with the Nordic Optical Telescope, operated on the island of La Palma jointly by Denmark, Finland, Iceland, Norway, and Sweden, in the Spanish Observatorio del Roque de los Muchachos of the Instiitute de Astrofisica de Canaries.