Bibcode
Rodríguez-Gil, P.; Gänsicke, B. T.; Hagen, H.-J.; Marsh, T. R.; Harlaftis, E. T.; Kitsionas, S.; Engels, D.
Referencia bibliográfica
Astronomy and Astrophysics, v.431, p.269-277 (2005)
Fecha de publicación:
2
2005
Revista
Número de citas
19
Número de citas referidas
15
Descripción
We report the discovery of a new, non-eclipsing SU UMa-type dwarf nova,
HS 2219+1824. Photometry obtained in quiescence
(V≈17.5) reveals a double-humped light curve from which we derive an
orbital period of ≃86.2 min. Additional photometry obtained during
a superoutburst reaching V≃12.0 clearly shows superhumps with a
period of ≃89.05 min. The optical spectrum contains double-peaked
Balmer and He I emission lines from the accretion disc as well as broad
absorption troughs of Hβ, Hγ, and Hδ from the white
dwarf primary star. Modelling of the optical spectrum implies a white
dwarf temperature of 13 000 K⪉Teff⪉17 000 K, a
distance of 180 pc⪉ d⪉230 pc, and suggests that the spectral
type of the donor star is later than M 5. Phase-resolved spectroscopy
obtained during quiescence reveals a narrow Hα emission line
component which has a radial velocity amplitude and phase consistent
with an origin on the secondary star, possibly on the irradiated
hemisphere facing the white dwarf. This constitutes the first detection
of line emission from the secondary star in a quiescent SU
UMa star.
Based in part on observations obtained at the German-Spanish
Astronomical Center, Calar Alto, operated by the Max-Planck-Institut
für Astronomie, Heidelberg, jointly with the Spanish National
Commission for Astronomy; on observations made with the IAC80 and OGS
telescopes, operated on the island of Tenerife by the Instituto de
Astrofísica de Canarias (IAC) and the European Space Agency
(ESA), respectively, in the Spanish Observatorio del Teide of the IAC;
on observations made at the 1.2 m telescope, located at Kryoneri
Korinthias, and owned by the National Observatory of Athens, Greece; and
on observations made with the William Herschel Telescope, which is
operated on the island of La Palma by the Isaac Newton Group in the
Spanish Observatorio del Roque de los Muchachos of the IAC.