CH Cygni X‐Ray Jet Activity and Multicomponent Structures

Karovska, M.; Carilli, Christopher L.; Raymond, J. C.; Mattei, J. A.

doi:10.1086/516772

Cited by 49 publications

(58 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In an extreme case of such interactions, the 2006 outburst of RS Oph triggered a shock wave that was seen at multiple wavelengths (e.g., O'Brien et al 2006). In the 2000-2002 outburst of Z And, a jet was seen at radio wavelengths (Brocksopp et al 2004), and it is known that jets from symbiotic binaries can produce faint X-rays (e.g., Galloway & Sokoloski 2004;Karovska et al 2007, 2010). Evidence for winds in symbiotic binaries, including AG Peg (Nussbaumer et al 1995), is widespread.…”

Section: The Origin Of the X-ray Emissionmentioning

confidence: 99%

Swiftobservations of the 2015 outburst of AG Peg – from slow nova to classical symbiotic outburst

Ramsay

Sokoloski

Luna

et al. 2016

Mon. Not. R. Astron. Soc.

View full text Add to dashboard Cite

Symbiotic stars often contain white dwarfs with quasi-steady shell burning on their surfaces. However, in most symbiotics, the origin of this burning is unclear. In symbiotic slow novae, however, it is linked to a past thermonuclear runaway. In June 2015, the symbiotic slow nova AG Peg was seen in only its second optical outburst since 1850. This recent outburst was of much shorter duration and lower amplitude than the earlier eruption, and it contained multiple peaks -like outbursts in classical symbiotic stars such as Z And. We report Swift X-ray and UV observations of AG Peg made between June 2015 and January 2016. The X-ray flux was markedly variable on a time scale of days, particularly during four days near optical maximum, when the X-rays became bright and soft. This strong X-ray variability continued for another month, after which the X-rays hardened as the optical flux declined. The UV flux was high throughout the outburst, consistent with quasi-steady shell burning on the white dwarf. Given that accretion disks around white dwarfs with shell burning do not generally produce detectable X-rays (due to Compton-cooling of the boundary layer), the X-rays probably originated via shocks in the ejecta. As the X-ray photoelectric absorption did not vary significantly, the X-ray variability may directly link to the properties of the shocked material. AG Peg's transition from a slow symbiotic nova (which drove the 1850 outburst) to a classical symbiotic star suggests that shell burning in at least some symbiotic stars is residual burning from prior novae.

show abstract

Section: The Origin Of the X-ray Emissionmentioning

confidence: 99%

Swiftobservations of the 2015 outburst of AG Peg – from slow nova to classical symbiotic outburst

Ramsay

Sokoloski

Luna

et al. 2016

Mon. Not. R. Astron. Soc.

View full text Add to dashboard Cite

show abstract

“…Leahy & Taylor 1987;Mukai et al 2009a), producing collimated outflows in the radio (e.g. Taylor et al 1986;Crocker et al 2001;Karovska et al 2007Karovska et al , 2010, because of a high orbital inclination (e.g. Skopal et al 1996).…”

Section: Ch Cygmentioning

confidence: 99%

Recent photometry of symbiotic stars

et al. 2012

View full text Add to dashboard Cite

We present new multicolour (UBVRCIC) photometric observations of classical symbiotic stars, EG And, Z And, BF Cyg, CH Cyg, CI Cyg, V1329 Cyg, TX CVn, AG Dra, Draco C1, AG Peg, and AX Per, carried out between 2007.1 and 2011.9. The aim of this paper is to present new data of our monitoring programme, to describe the main features of their light curves (LC) and to point problems for their future investigation. The data were obtained by the method of the classical photoelectric and CCD photometry.

show abstract

“…In both systems, the hot component is an accreting white dwarf showing spectacular activity: irregular accretion-powered outbursts accompanied by massive outflows and jets (e.g. Kellogg et al 2007;Karovska et al 2007, and references therein). The cool component in R Aqr is a Mira variable with a pulsation period of 387 d , whereas in CH Cyg it is an M7 III semiregular variable with complex variability (e.g.…”

Section: Introductionmentioning

confidence: 99%

CO observations of symbiotic stellar systems

Bujarrabal

Mikołajewska

Quintana-Lacaci

2010

A&A

View full text Add to dashboard Cite

Aims. We have studied the molecular content of the circumstellar environs of symbiotic stellar systems, in particular of the well know objects R Aqr and CH Cyg. The study of molecules in these stars will help for understanding the properties of the very inner shells around the cool stellar component from which molecular emission is expected to come. Methods. We performed mm-wave observations with the IRAM 30 m telescope of the 12 CO J = 1−0 and J = 2−1, 13 CO J = 1−0 and J = 2−1, and SiO J = 5−4 transitions in the symbiotic stars R Aqr, CH Cyg, and HM Sge. The data were analyzed by means of a simple analytical description of the general properties of molecular emission from the inner shells around the cool star. Numerical calculations of the expected line profiles were also performed that took the level population and radiative transfer under such conditions into account. Results. Weak emission of 12 CO J = 1−0 and J = 2−1 was detected in R Aqr and CH Cyg and a good line profile of 12 CO J = 2−1 in R Aqr was obtained. The intensities and profile shapes of the detected lines are compatible with emission coming from a very small shell around the Mira-type star, with a radius comparable to or slightly smaller than the distance to the hot dwarf companion, 10 14 −2 × 10 14 cm. We argue that other possible explanations are improbable. This region probably shows properties similar to those characteristic of the inner shells around standard AGB stars: outwards expansion at about 5-25 km s −1 , with a significant acceleration of the gas, temperatures decreasing with radius between about 1000 and 500 K, and densities ∼10 9 −3 × 10 8 cm −3 . Our model calculations are able to explain the asymmetric line shape observed in 12 CO J = 2−1 from R Aqr, in which the relatively weaker blue part of the profile would result from selfabsorption by the outer layers (in the presence of a velocity increase and a temperature decrease with radius). The mass-loss rates are somewhat higher than in standard AGB stars, as often happens for symbiotic systems. In R Aqr, we find that the total mass of the CO emitting region is ∼2−3 × 10 −5 M , corresponding toṀ ∼ 5 × 10 −6 −10 −5 M yr −1 and compatible with results obtained from dust emission. Considering other existing data on molecular emission, we suggest that the limited extent of the molecule-rich gas in symbiotic systems is mainly due to molecule photodissociation by the radiation of the hot dwarf star.

show abstract

CH Cygni X‐Ray Jet Activity and Multicomponent Structures

Cited by 49 publications

References 28 publications

Swiftobservations of the 2015 outburst of AG Peg – from slow nova to classical symbiotic outburst

Swiftobservations of the 2015 outburst of AG Peg – from slow nova to classical symbiotic outburst

Recent photometry of symbiotic stars

CO observations of symbiotic stellar systems

Contact Info

Product

Resources

About