Accretion in the detached post-common-envelope binary LTT 560

Tappert, C.; Gänsicke, B. T.; Schmidtobreick, L.; Ribeiro, T.

doi:10.1051/0004-6361/201116436

Cited by 24 publications

(32 citation statements)

References 36 publications

(47 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A similar narrow emission line originating from near the white dwarf is seen in some detached post‐common‐envelope binaries (e.g. LTT 560; Tappert et al , but see also Tappert et al and fig. 8 of Gänsicke et al ).…”

Section: Analysis and Resultssupporting

confidence: 53%

CSS100603:112253−111037: a helium-rich dwarf nova with a 65 min orbital period

Breedt

Gänsicke

Marsh

et al. 2012

Monthly Notices of the Royal Astronomical Society

Self Cite

View full text Add to dashboard Cite

We present time‐resolved optical spectroscopy of the dwarf nova CSS100603:112253−111037. Its optical spectrum is rich in helium, with broad, double‐peaked emission lines produced in an accretion disc. We measure a line flux ratio He i λ5876/Hα = 1.49 ± 0.04, a much higher ratio than is typically observed in dwarf novae. The orbital period, as derived from the radial velocity of the line wings, is 65.233 ± 0.015 min. In combination with the previously measured superhump period, this implies an extreme mass ratio of M2/M1 = 0.017 ± 0.004. The Hα and He i λ 6678 emission lines additionally have a narrow central spike, as is often seen in the spectra of AM CVn‐type stars. Comparing their properties with cataclysmic variables (CVs), AM CVn systems and hydrogen binaries below the CV period minimum, we argue that CSS100603:112253−111037 is the first compelling example of an AM CVn system forming via the evolved CV channel. With the addition of this system, evolved CVs now account for 7 per cent of all known semidetached white dwarf binaries with Porb < 76 min. Two recently discovered binaries may further increase this figure. Although the selection bias of this sample is not yet well defined, these systems support the evolved CV model as a possible formation channel for ultracompact accreting binaries. The orbital periods of the three ultracompact hydrogen accreting binaries overlap with those of the long‐period AM CVn stars, but there are currently no known systems in the period range of 67–76 min.

show abstract

Section: Analysis and Resultssupporting

confidence: 53%

CSS100603:112253−111037: a helium-rich dwarf nova with a 65 min orbital period

Breedt

Gänsicke

Marsh

et al. 2012

Monthly Notices of the Royal Astronomical Society

Self Cite

View full text Add to dashboard Cite

show abstract

“…These emission lines originate from the white dwarf's chromosphere as a result of accretion of material from the wind of the M star. They have been seen in other close white dwarf plus main‐sequence binaries and reliably track the motion of the white dwarf (Tappert et al ). A list of the unambiguously detected emission lines from the white dwarf is given in Table , though there are likely to be additional lines at longer wavelengths which are obscured by the dominant M star.…”

Section: Resultsmentioning

confidence: 81%

An accurate mass and radius measurement for an ultracool white dwarf

Parsons

Gänsicke²,

Marsh³

et al. 2012

Monthly Notices of the Royal Astronomical Society

Self Cite

View full text Add to dashboard Cite

Studies of cool white dwarfs in the solar neighbourhood have placed a limit on the age of the Galactic disk of 8-9 billion years. However, determining their cooling ages requires the knowledge of their effective temperatures, masses, radii, and atmospheric composition. So far, these parameters could only be inferred for a small number of ultracool white dwarfs for which an accurate distance is known, by fitting their spectral energy distributions (SEDs) in conjunction with a theoretical mass-radius relation. However, the mass-radius relation remains largely untested, and the derived cooling ages are hence model-dependent. Here we report direct measurements of the mass and radius of an ultracool white dwarf in the double-lined eclipsing binary SDSS J013851.54-001621.6. We find M(WD)=0.529+/-0.010Msol and R(WD)=0.0131+/-0.0003Rsol. Our measurements are consistent with the mass-radius relation and we determine a robust cooling age of 9.5 billion years for the 3570K white dwarf. We find that the mass and radius of the low mass companion star, M(sec)=0.132+/-0.003Msol and R(sec)=0.165+/-0.001Rsol, are in agreement with evolutionary models. We also find evidence that this >9.5 Gyr old M5 star is still active, far beyond the activity lifetime for a star of its spectral type. This is likely caused by the high tidally-enforced rotation rate of the star. The companion star is close to filling its Roche lobe and the system will evolve into a cataclysmic variable in only 70 Myr. Our direct measurements demonstrate that this system can be used to calibrate ultracool white dwarf atmospheric models.Comment: 9 pages, 9 figures and 4 tables. Accepted for publication in MNRA

show abstract

“…detached WD/M-dwarf binaries) in low states, where they originate either on or close to the WD (e.g. Tappert et al 2007Tappert et al , 2011Parsons et al 2012Parsons et al , 2013 or from material located between the two stars (e.g. Gänsicke et al 1998;O'Donoghue et al 2003;Parsons et al 2011).…”

Section: Averaged Spectra Of Ec21178-5417mentioning

confidence: 99%

A spectroscopic analysis of the eclipsing nova-like EC 21178−5417 – discovery of spiral density structures

Khangale

Woudt

Potter

et al. 2020

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

We present phase-resolved optical spectroscopy of the eclipsing nova-like cataclysmic variable EC21178-5417 obtained between 2002 and 2013. The average spectrum of EC21178-5417 shows broad double-peaked emission lines from HeII 4686Å (strongest feature) and the Balmer series. The high-excitation feature, CIII/NIII at 4640-4650Å, is also present and appears broad in emission. A number of other lines, mostly HeI, are clearly present in absorption and/or emission. The average spectrum of EC21178-5417 taken at different months and years shows variability in spectral features, especially in the Balmer lines beyond Hγ, from pure line emission, mixed line absorption and emission to pure absorption lines. Doppler maps of the HeII 4686Å emission reveal the presence of a highly-inclined asymmetric accretion disc and a two spiral armlike structure, whereas that of the Balmer lines (Hα and Hβ) reveal a more circular accretion disc. There is no evidence of a bright spot in the Doppler maps of EC21178-5417 and no emission from the secondary star is seen in the tomograms of the HeII 4686Å and Balmer lines. Generally, the emission in EC21178-5417 is dominated by emission from the accretion disc. We conclude that EC21178-5417 is a member of the RW Tri or UX UMa sub-type of nova-like variables based on these results and because it shows different spectral characteristics at different dates. This spectral behaviour suggests that EC21178-5417 undergoes distinct variations in mass transfer rate on the observed time scales of months and years.

show abstract

Accretion in the detached post-common-envelope binary LTT 560

Cited by 24 publications

References 36 publications

CSS100603:112253−111037: a helium-rich dwarf nova with a 65 min orbital period

CSS100603:112253−111037: a helium-rich dwarf nova with a 65 min orbital period

An accurate mass and radius measurement for an ultracool white dwarf

A spectroscopic analysis of the eclipsing nova-like EC 21178−5417 – discovery of spiral density structures

Contact Info

Product

Resources

About