Simultaneous <i>UBVRI</i> observations of the cataclysmic variable AE Aquarii: Temperatures and masses of fireballs

Zamanov, R.; Latev, G.; Stoyanov, K. A.; Boeva, S.; Spassov, B.; Tsvetkov, S. V.

doi:10.1002/asna.201211718

Cited by 4 publications

(5 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…State switches can occur on a time scale of about one or two weeks (see for example HS 0943+1404; Rodríguez-Gil et al 2005) but large amplitude variations in time-scales of tens of min-utes have also been observed for magnetic CVs (like in AE Aqr e.g. Zamanov et al 2012); if W2 is an intermediate polar (the presence of a disk is required to account for the observed/unobserved eclipses at different epochs), we could have caught the system during a high/low state transition.…”

Section: Cvs With Large-amplitude Nuv Variabilitymentioning

confidence: 99%

New cataclysmic variables and other exotic binaries in the globular cluster 47 Tucanae*

Sandoval

Berg

Heinke

et al. 2018

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

We present 22 new (+3 confirmed) cataclysmic variables (CVs) in the non corecollapsed globular cluster 47 Tucanae (47 Tuc). The total number of CVs in the cluster is now 43, the largest sample in any globular cluster so far. For the identifications we used near-ultraviolet (NUV) and optical images from the Hubble Space Telescope, in combination with X-ray results from the Chandra X-ray Observatory. This allowed us to build the deepest NUV CV luminosity function of the cluster to date. We found that the CVs in 47 Tuc are more concentrated towards the cluster center than the main sequence turnoff stars. We compared our results to the CV populations of the core-collapsed globular clusters NGC 6397 and NGC 6752. We found that 47 Tuc has fewer bright CVs per unit mass than those two other clusters. That suggests that dynamical interactions in core-collapsed clusters play a major role creating new CVs. In 47 Tuc, the CV population is probably dominated by primordial and old dynamically formed systems. We estimated that the CVs in 47 Tuc have total masses of ∼ 1.4 M . We also found that the X-ray luminosity function of the CVs in the three clusters is bimodal. Additionally, we discuss a possible double degenerate system and an intriguing/unclassified object. Finally, we present four systems that could be millisecond pulsar companions given their X-ray and NUV/optical colors. For one of them we present very strong evidence for being an ablated companion. The other three could be CO-or He-WDs.

show abstract

Section: Cvs With Large-amplitude Nuv Variabilitymentioning

confidence: 99%

New cataclysmic variables and other exotic binaries in the globular cluster 47 Tucanae*

Sandoval

Berg

Heinke

et al. 2018

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

show abstract

“…Pearson et al (2003) have suggested that the flares of AE Aqr are due to the ejection and expansion of isothermal fireballs. Using their improved model (Pearson et al 2005), Zamanov et al (2012) have estimated the fireballs temperatures of 10000–25000 K, masses of (7–90) ×10 19 g, and sizes of (3–7) ×10 9 cm (using a distance of d =86 pc). These values refer to the peak of the flares observed in the UBVRI bands.…”

Section: Color–magnitude Diagrammentioning

confidence: 99%

“…Journal of observations is given in Table 1. The first four dates are partly analyzed in Zamanov et al (2012). Table 1 Simultaneous observations of AE Aqr in B and V bands.…”

Section: Observationsmentioning

confidence: 99%

“…In the optical bands, AE Aqr exhibits atypical flickering consisting of large optical flares with amplitude ⩽1 magnitude in the Johnson V band. The flares are visible about one‐third of the time and have typical rise times of 200−−400 s (van Paradijs et al 1989; Zamanov et al 2012). The flares are also visible in the X‐ray (Mauche et al 2012) and submillimeter wavelengths (Torkelsson 2013).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

The cataclysmic variable AE Aquarii: B–V color of the flares

et al. 2017

Self Cite

View full text Add to dashboard Cite

We report simultaneous observations of the flaring behavior of the cataclysmic variable star AE Aquarii (AE Aqr). The observations are in Johnson B and V bands. The color-magnitude diagrams (B-V vs. V and B-V vs. B) show that the star becomes more blue as it becomes brighter. In our model, AE Aqr's behavior can be explained with flares (fireballs) with 0.03 ≤ B-V ≤ 0.30, and temperature in the interval 8000 ≤ T ≤ 12000. 1 How to cite this article: Zamanov RK, Latev GY, Boeva S, Ibryamov S, Nikolov GB, Stoyanov KA. The cataclysmic variable AE Aquarii: B-V color of the flares. Astron. Nachr. / AN. 2017;338:598-603.

show abstract

“…Our model can be compared with the model of colliding blobs (e.g., Wynn et al 1997). In this model, it is suggested that matter accretes onto the magnetosphere in blobs, which are subsequently ejected by the propelling magnetosphere in clumps, which collide with each other and radiate (e.g., Pearson et al 2003;Zamanov et al 2012). To explain the observed flares, they estimate the mass involved in collisions as ∆M ≈ 3 × 10 19 g and the total energy, released during collisions, as E ≈ 3 × 10 33 erg/s.…”

Section: Energy In Flaresmentioning

confidence: 99%

Comparisons of MHD propeller model with observations of cataclysmic variable AE Aqr

Blinova

Romanova

Ustyugova

et al. 2019

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

We have developed a numerical MHD model of the propeller candidate star AE Aqr using axisymmetric magneto-hydrodynamic (MHD) simulations. We suggest that AE Aqr is an intermediate polar-type star, where the magnetic field is relatively weak and an accretion disc may form around the white dwarf. The star is in the propeller regime, and many of its observational properties are determined by the disc-magnetosphere interaction. Comparisons of the characteristics of the observed versus modelled AE Aqr star show that the model can explain many observational properties of AE Aqr. In a representative model, the magnetic field of the star is B ≈ 3.3 × 10 5 G and the time-averaged accretion rate in the disc is 5.5 × 10 16 g/s. Most of this matter is ejected into conically-shaped winds. The numerical model explains the rapid spin-down of AE Aqr through the outflow of angular momentum from the surface of the star to the wind, corona and disc. The energy budget in the outflows, 9 × 10 33 erg/s, is sufficient for explaining the observed flaring radiation in different wavebands. The time scale of ejections into the wind matches the short time scale variability in the light curves of AE Aqr.

show abstract

Simultaneous UBVRI observations of the cataclysmic variable AE Aquarii: Temperatures and masses of fireballs

Cited by 4 publications

References 38 publications

New cataclysmic variables and other exotic binaries in the globular cluster 47 Tucanae*

New cataclysmic variables and other exotic binaries in the globular cluster 47 Tucanae*

The cataclysmic variable AE Aquarii: B–V color of the flares

Comparisons of MHD propeller model with observations of cataclysmic variable AE Aqr

Contact Info

Product

Resources

About