A 9-h CV with one outburst in 4 yr of Kepler data

Yu, Zhifei; Thorstensen, J. R.; Rappaport, S.; Mann, Andrew W.; Jacobs, T.; Nelson, L. A.; Gänsicke, B. T.; LaCourse, D.; Borkovits, T.; Steeghs, D.; Toloza, Odette; Vanderburg, Andrew; Lin, D. N. C.

doi:10.1093/mnras/stz2094

Cited by 19 publications

(16 citation statements)

References 89 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Furthermore, the eclipse profile in Fig. 4 lacks disk characteristics as the wide rounded-off component observed in IPHAS J0627 (Aungwerojwit et al 2012) or the V-shaped eclipse of KIC 5608384 (Yu et al 2019). Any disk component is, furthermore, limited to stay below the minima of the spin modulation.…”

Section: Is There An Accretion Disk?mentioning

confidence: 93%

J1832.4-1627, the first eclipsing stream-fed intermediate polar

Beuermann

Breitenstein²,

Schwab

2022

A&A

View full text Add to dashboard Cite

We present a photometric study of the newly discovered eclipsing intermediate polar J183221.56-162724.25 (in short J1832) with an orbital period of 8.87 h. The system features a box-like deep eclipse with a full width at 50% depth of 1970 ± 2 s and a large-amplitude coherent pulsation with Pobs = 65.18 min, which represents either the synodic (beat) period or the spin period of the white dwarf (WD). The period ratio is either Pspin/Porb = 0.1091 or 0.1225, respectively. The eclipsed light originates almost entirely from the two accretion spots and columns on the WD, with characteristics indicative of pole flipping. There is no evidence for an accretion disk, and we identify J1832 as the first deeply eclipsing stream-fed intermediate polar. Our grizy photometry in eclipse yielded an i-band AB magnitude of the Roche-lobe-filling secondary star of 18.98(3), an extinction EB − V = 0.54 ± 0.17, and a spectral type ∼K6. Dynamic models, fitting the photometry, limit the distance to between 1270 and 2500 pc for masses of the secondary star, M2, between 0.16 and 1.0 M⊙, well within the Gaia EDR3 confidence limits. Employing a luminosity selection inspired by binary population studies yields a mean M2 = 0.32 M⊙ with a 2σ upper limit of 0.60 M⊙ and a mean distance d = 1596 pc with a 2σ upper limit of 1980 pc. The secondary star is located in its Hertzsprung-Russell diagram at a mean Teff, 2 = 4120 K and log(L2/L⊙) = − 0.92, from where the binary can evolve into either a polar or an ultracompact binary with a highly magnetic primary. The system displays a variable accretion rate, lapses repeatedly into short-lived low states of negligible accretion, and currently displays an orbital period that decreases on a timescale of τ ∼ 3 × 105 yr. X-ray observations, optical spectroscopy, and spectropolarimetry have a high potential for studies of the properties of J1832 as an individual object and of stream-fed accretion in general.

show abstract

Section: Is There An Accretion Disk?mentioning

confidence: 93%

J1832.4-1627, the first eclipsing stream-fed intermediate polar

Beuermann

Breitenstein²,

Schwab

2022

A&A

View full text Add to dashboard Cite

show abstract

“…1RXH J082623.6−505741 is more akin to the nearby 11 hr orbital period cataclysmic variable EY Cyg (629 ± 7 pc; Bailer-Jones et al 2021) having a late-G-/early-K-type secondary (Echevarría et al 2007), L X ∼ 10 32 erg s −1 (Nabizadeh & Balman 2020), and a dwarf nova recurrence time >5 yr (Tovmassian et al 2002) (Bahramian et al 2021), while KIC 5608384 had a single 5 day dwarf nova outburst over 4 yr of data (Yu et al 2019). These systems deviate from the relation of Britt et al (2015), predicting that X-ray-bright dwarf novae should have frequent outbursts.…”

Section: Context and Implicationsmentioning

confidence: 99%

“…The low mass-transfer rates for these binaries are not well explained by theory. For example, Yu et al (2019) construct custom MESA models of the evolution of KIC 5608384 and find a predicted current mass-transfer rate that is a factor of 20 higher than the observed rate of ∼3 × 10 −10 M e yr −1 . For any individual system, it is difficult to rule out stochastic variations around the mean mass-transfer rate, but the accumulating number of cataclysmic variables with these properties means that the observed mass-transfer rates should be taken more seriously.…”

Section: Context and Implicationsmentioning

confidence: 99%

“…For any individual system, it is difficult to rule out stochastic variations around the mean mass-transfer rate, but the accumulating number of cataclysmic variables with these properties means that the observed mass-transfer rates should be taken more seriously. These values affect not only the interpretation of the current state of the binaries, but also their future evolution, such as whether they become degenerate AM CVn systems or not (e.g., Goliasch & Nelson 2015;Kalomeni et al 2016;Yu et al 2019).…”

Section: Context and Implicationsmentioning

confidence: 99%

See 1 more Smart Citation

1RXH J082623.6–505741: A New Long-period Cataclysmic Variable with an Evolved Donor and a Low Mass-transfer Rate

Sokolovsky

Strader

Swihart

et al. 2022

ApJ

View full text Add to dashboard Cite

We report the discovery of 1RXH J082623.6−505741, a 10.4 hr orbital period compact binary. Modeling extensive optical photometry and spectroscopy reveals a ∼0.4 M ⊙ K-type secondary transferring mass through a low-state accretion disk to a nonmagnetic ∼0.8 M ⊙ white dwarf. The secondary is overluminous for its mass and dominates the optical spectra at all epochs and must be evolved to fill its Roche Lobe at this orbital period. The X-ray luminosity L X ∼ 1–2 × 1032 erg s−1 derived from both new XMM-Newton and archival observations, although high compared to most CVs, still only requires a modest accretion rate onto the white dwarf of M ̇ ∼ 3 × 10−11 to 3 × 10−10 M ⊙ yr−1, lower than expected for a cataclysmic variable with an evolved secondary. No dwarf nova outbursts have yet been observed from the system, consistent with the low derived mass-transfer rate. Several other cataclysmic variables with similar orbital periods also show unexpectedly low mass-transfer rates, even though selection effects disfavor the discovery of binaries with these properties. This suggests the abundance and evolutionary state of long-period, low mass-transfer rate cataclysmic variables are worthy of additional attention.

show abstract

“…Breedt et al 2014). Recently, Yu et al (2019) discovered a longperiod CV (𝑃 orb ∼ 9 hours) with only one outburst in 4 years of nearly continuous Kepler data. The expected future evolution of that system is similar to what we infer for J0140.…”

Section: Is J0140 Detached or Mass-transferring?mentioning

confidence: 99%

LAMOST J0140355+392651: An evolved cataclysmic variable donor transitioning to become an extremely low mass white dwarf

El-Badry,

Quataert,

Rix

et al. 2021

Preprint

View full text Add to dashboard Cite

We present LAMOST J0140355+392651 (hereafter J0140), a close (𝑃 orb = 3.81 hours) binary containing a bloated, low-mass (𝑀 ≈ 0.15𝑀 ) proto-white dwarf (WD) and a massive (𝑀 ≈ 0.95 𝑀 ) WD companion. The system's optical light curve is dominated by large-amplitude ellipsoidal variability but also exhibits additional scatter, likely driven by pulsations. The proto-WD is cooler (𝑇 eff = 6800 ± 100 K) and more puffy (log 𝑔/ cm s −2 = 4.74 ± 0.07) than any known extremely low mass (ELM) WD, but hotter than any known cataclysmic variable (CV) donor. It either completely or very nearly fills its Roche lobe (𝑅/𝑅 Roche lobe = 0.99 ± 0.01), suggesting ongoing or recently terminated mass transfer. No dwarf nova-like outbursts have been observed. The spectrum is dominated by the proto-WD but shows tentative hints of H𝛼 emission, perhaps due to accretion onto the massive WD. The properties of the system are well-matched by MESA binary evolution models of CVs with donors that underwent significant nuclear evolution before the onset of mass transfer. In these models, the bloated proto-WD is either still losing mass via stable Roche lobe overflow or was doing so until very recently. In either case, it is evolving toward higher temperatures at near-constant luminosity to become an ELM WD. If the system is detached, mass transfer likely ended when the donor became too hot for magnetic braking to remain efficient. Evolutionary models predict that the binary will shrink to 𝑃 orb 10 minutes within a few Gyr, when it will either merge or become an AM CVn binary. J0140 provides an observational link between the formation channels of CVs, ELM WDs, detached ultracompact WD binaries, and AM CVn systems.

show abstract

A 9-h CV with one outburst in 4 yr of Kepler data

Cited by 19 publications

References 89 publications

J1832.4-1627, the first eclipsing stream-fed intermediate polar

J1832.4-1627, the first eclipsing stream-fed intermediate polar

1RXH J082623.6–505741: A New Long-period Cataclysmic Variable with an Evolved Donor and a Low Mass-transfer Rate

LAMOST J0140355+392651: An evolved cataclysmic variable donor transitioning to become an extremely low mass white dwarf

Contact Info

Product

Resources

About