Confirmation of Eclipses in KPD 0422+5421, A Binary Containing a White Dwarf and a Subdwarf B Star

@article{Orosz1999ConfirmationOE,
  title={Confirmation of Eclipses in KPD 0422+5421, A Binary Containing a White Dwarf and a Subdwarf B Star},
  author={Jerome A. Orosz and Richard W. Pogge The Ohio State University and Utrecht University},
  journal={Monthly Notices of the Royal Astronomical Society},
  year={1999},
  volume={310},
  pages={773-783}
}
We report additional photometric CCD observations of KPD 0422+5421, a binary with an orbital period of 2.16 hours which contains a subdwarf B star (sdB) and a white dwarf. There are two main results of this work. First, the light curve of KPD 0422+5421 contains two distinct periodic signals, the 2.16 hour ellipsoidal modulation discovered by Koen, Orosz, & Wade (1998) and an additional modulation at 7.8 hours. This 7.8 hour modulation is clearly not sinusoidal: the rise time is about 0.25 in… Expand

Figures and Tables from this paper

Orbital Parameters for the Black Hole Binary XTE J1650–500*
We present R-band photometry of the X-ray transient and candidate black hole binary XTE J1650-500 obtained between 2003 May and August with the 6.5 m Clay telescope. A timing analysis of these dataExpand
KPD 1930+2752: a candidate Type Ia supernova progenitor
We present spectra of the pulsating sdB star KPD 1930+2752 which confirm that this star is a binary. The radial velocities measured from the Hα and He i 6678-A spectral lines vary sinusoidally withExpand
Discovery and Asteroseismological Analysis of the Pulsating sdB Star PG 0014+067*
We report the discovery of low-amplitude, short-period, multiperiodic luminosity variations in the hot B subdwarf PG 0014+067. This star was selected as a potential target in the course of ourExpand
Optical and Infrared Photometry of the Microquasar GRO J1655-40 in Quiescence
We present BVIJK photometry of the black hole candidate GRO J1655-40 in full quiescence. We report a refined orbital period of 2.62191 ± 0.00020 days. The light curves are dominated by ellipsoidalExpand
The hot subdwarf B + white dwarf binary KPD 1930+2752 A supernova type Ia progenitor candidate ,,, †
Context. The nature of the progenitors of type Ia supernovae is still under debate. KPD 1930+2752 is one of the best SN Ia progenitor candidates known today. The object is a double degenerate systemExpand
The long-period orbit of the dwarf nova V630 Cassiopeiae
We present extensive spectroscopy and photometry of the dwarf nova V630 Cassiopeiae. A late-type (K4–5) absorption spectrum is easily detectable, from which we derive the orbital parameters. We findExpand
Hot subdwarf stars in close-up view I. Rotational properties of subdwarf B stars in close binary systems and nature of their unseen companions
The origin of hot subdwarf B stars (sdBs) is still unclear. About half of the known sdBs are in close binary systems for which common envelope ejection is the most likely formation channel. Little isExpand
New binaries among UV-selected, hot subdwarf stars and population properties
We have measured the orbital parameters of seven close binaries, including six new objects,in a radial velocity survey of 38 objects comprising a hot subdwarf star with orbital periods ranging fromExpand
Gravitational lensing in eclipsing binary stars
I consider the effect of the gravitational deflection of light upon the light curves of eclipsing binary stars, focusing mainly upon systems containing at least one white dwarf component. In absoluteExpand
Orbital periods of 22 subdwarf B stars
Subdwarf B (sdB) stars are thought to be core helium burning stars with low mass hydrogen envelopes. In recent years it has become clear that many sdB stars lose their hydrogen through interactionExpand
...
1
2
3
4
5
...

References

SHOWING 1-10 OF 30 REFERENCES
KPD 0422+5421: a new short-period subdwarf B/white dwarf binary
The sdB star KPD 0422+5421 was discovered to be a single-lined spectroscopic binary with a period of P = 0.0901795±(3×10 −7 ) days (2 hours, 10 minutes). The U and B light curves display anExpand
Detection of p-Mode Pulsations in the Hot Subdwarf B Star KPD 2109+4401
We report the discovery of multiperiodic luminosity variations in the hot B subdwarf KPD 2109+4401. At least five periodicities are seen in the light curve, from 182.5 to 198.4 s. The largestExpand
Discovery of p-Mode Instabilities in the Hot Subdwarf B Star PG 1047+003
We report the discovery of multiperiodic luminosity variations in the hot B subdwarf PG 1047+003. At least five periodicities are seen in the light curve, from 104.2 s to 161.9 s, but others are alsoExpand
Atmospheric parameters of field subdwarf B stars
High signal-to-noise ratio optical spectrophotometry of a sample of field subluminous B stars drawn largely from the Palomar Green ultraviolet-excess survey is analyzed with a new grid of modelExpand
The KPD Survey for Galactic Plane Ultraviolet-Excess Objects: Space Densities of White Dwarfs and Subdwarfs
A survey for ultraviolet-excess objects has been performed for over about 1000 sq deg of the Galactic plane. Photographic blue and ultraviolet plates were obtained to select ultraviolet-excessExpand
New limb-darkening coefficients for modeling binary star light curves
We present monochromatic, passband-specific, and bolometric limb-darkening coefficients for a linear as well as nonlinear logarithmic and square root limb-darkening laws. These coefficients,Expand
A Dynamical Study of Merger Remnants
The velocity dispersion of objects from the Arp and the Arp-Madore atlases that have characteristics of recently merged galaxies is measured. These data are used to test the hypothesis that theExpand
Evolution of Helium White Dwarfs of Low and Intermediate Masses
We present detailed calculations of the evolution of low-mass, helium white dwarf models with masses from M = 0.1 to M = 0.5 M? at intervals of 0.05 M? and with a metallicity of Z = 10-3. For thisExpand
Evolution of DA white dwarfs in the context of a new theory of convection
In this study we compute the structure and evolution of carbon-oxygen DA white dwarfs by means of a detailed and updated evolutionary code. We treat the energy transport by convection within theExpand
Grids of white dwarf evolutionary models with masses from M=0.1 to 1.2 m⊙
We present detailed evolutionary calculations for carbon--oxygen- and helium-core white dwarf models with masses ranging from M= 0.1 to 1.2 M⊙ and for metallicities Z = 0.001 and 0. The sequencesExpand
...
1
2
3
...