Strong dust processing in circumstellar discs   around 6 RV Tauri stars

Ruyter, S. De; Winckel, H. Van; Dominik, C.; Waters, L.B.F.M.; Dejonghe, Herwig

doi:10.1051/0004-6361:20041989

Cited by 56 publications

(73 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Many of them have already been given a disc status in the literature (de Ruyter et al 2006;De Ruyter et al 2005). The 63 (50%) RV Tauri stars, in the non-IR box do not display any IR excess at all, also not when considering their full SED.…”

Section: Rv Tauri Starsmentioning

confidence: 99%

TheWISEview of RV Tauri stars

Gezer

Winckel

Bozkurt

et al. 2015

Mon. Not. R. Astron. Soc.

Self Cite

128

View full text Add to dashboard Cite

We present a detailed study based on infrared photometry of all Galactic RV Tauri stars from the General Catalogue of Variable Stars (GCVS). RV Tauri stars are the brightest among the population II Cepheids. They are thought to evolve away from the asymptotic giant branch (AGB) towards the white dwarf domain. IRAS detected several RV Tauri stars because of their large IR excesses and it was found that they occupy a specific region in theWe used the all sky survey of WISE to extend these studies and compare the infrared properties of all RV Tauri stars in the GCVS with a selected sample of post-AGB objects with the goal to place the RV Tauri pulsators in the context of post-AGB evolution. Moreover, we correlated the IR properties of both the RV Tauri stars and the comparison sample with other observables like binarity and the presence of a photospheric chemical anomaly called depletion. We find that Galactic RV Tauri stars display a range of infrared properties and we differentiate between disc sources, objects with no IR excess and objects for which the spectral energy distribution (SED) is uncertain. We obtain a clear correlation between disc sources and binarity. RV Tauri stars with a variable mean magnitude are exclusively found among the disc sources. We also find evidence for disc evolution among the binaries. Furthermore our studies show that the presence of a disc seems to be a necessary but not sufficient condition for the depletion process to become efficient.

show abstract

Section: Rv Tauri Starsmentioning

confidence: 99%

TheWISEview of RV Tauri stars

Gezer

Winckel

Bozkurt

et al. 2015

Mon. Not. R. Astron. Soc.

Self Cite

128

View full text Add to dashboard Cite

show abstract

“…Contrary to U Mon, R Sct has not been found to be part of a binary system (de Ruyter et al 2005). The latter authors also pointed out the much lower dust excess in R Sct compared to U Mon with drastically different spectral energy distributions.…”

Section: Discussionmentioning

confidence: 90%

“…Our magnetic field measurements in the photosphere of U Mon and R Sct support the use of weak fields in MHD models. In addition, de Ruyter et al (2005) suggested that U Mon hosts a "non-spherically symmetric circumstellar dust distribution" based on the comparison of its large IR excess and the lack of line-of-sight reddening. The strong Stokes Q and U profiles presented in Fig.…”

Section: Influence Of the Weak Field On The Dynamicsmentioning

confidence: 99%

First detection of surface magnetic fields in post-AGB stars: the cases of U Monocerotis and R Scuti

Sabin¹,

Wade²,

Lèbre³

2014

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

While several observational investigations have revealed the presence of magnetic fields in the circumstellar envelopes, jets and outflows of post-Asymptotic Giant Branch stars (PAGBs) and planetary nebulae (PNe), none has clearly demonstrated their presence at the stellar surface. The lack of information on the strength of the surface magnetic fields prevents us from performing any thorough assessment of their dynamic capability (i.e. material mixing, envelope shaping, etc). We present new high resolution spectropolarimetric (Stokes V ) observations of a sample of PAGB stars, realised with the instruments ESPaDOnS and Narval, where we searched for the presence of photospheric magnetic fields. Out of the seven targets investigated the RV Tauri stars U Mon and R Sct display a clear Zeeman signature and return a definite detection after performing a least squares deconvolution (LSD) analysis. The remaining five PAGBs show no significant detection. We derived longitudinal magnetic fields of 10.2 ± 1.7 G for U Mon and 0.6 ± 0.6 G for R Sct. In both cases the Stokes profiles point towards an interaction of the magnetic field with the atmosphere dynamics. This first discovery of weak magnetic fields (i.e. ∼10 gauss level) at the stellar surface of PAGB stars opens the door to a better understanding of magnetism in evolved stars.

show abstract

“…The discs are spatially resolved, but this is only detectable using interferometric techniques (Deroo et al 2006(Deroo et al , 2007, and they typically have a radius of only 50 AU at 10 μm. The high dust-grain processing is an observational indication that the compact discs are stable (De Ruyter et al 2005;Gielen et al 2008Gielen et al , 2009. Since the discovery of the binary nature of a small sample of the most depleted objects (Van Winckel et al 1995), this binary nature of the disc sources has been further confirmed ).…”

Section: Introductionmentioning

confidence: 94%

The optically bright post-AGB population of the LMC

Aarle

Winckel

Evans

et al. 2011

A&A

Self Cite

109

View full text Add to dashboard Cite

Context. The detected variety in chemistry and circumstellar shell morphology of the limited sample of Galactic post-asymptotic giant branch (AGB) stars is so large that there is no consensus yet on how the different objects are linked by evolutionary channels. The evaluation is complicated by the fact that their distances and hence luminosities remain largely unknown. Aims. We construct a catalogue of the optically bright post-AGB stars in the Large Magellanic Cloud (LMC). The sample forms an ideal testbed for stellar evolution theory predictions of the final phase of low-and intermediate-mass stars, because the distance and hence luminosity and also the current and initial mass of these objects is well constrained. Methods. Via cross-correlation of the Spitzer SAGE catalogue with optical catalogues we selected a sample of LMC post-AGB candidates based on their [8] − [24] colour index and estimated luminosity. We determined the fundamental properties of the central stars of 105 of these objects using low-resolution, optical spectra that we obtained at Siding Spring Observatory and SAAO. Results. We constructed a catalogue of 70 high probability and 1337 candidate post-AGB stars that is available at the CDS. About half of the objects in our sample of post-AGB candidates show a spectral energy distribution (SED) that is indicative of a disc rather than an expanding and cooling AGB remnant. Like in the Galaxy, the disc sources are likely associated with binary evolution. Important side products of this research are catalogues of candidate young stellar objects, candidate supergiants with circumstellar dust, and discarded objects for which a spectrum was obtained. These too are available at the CDS.

show abstract

Strong dust processing in circumstellar discs around 6 RV Tauri stars

Cited by 56 publications

References 26 publications

TheWISEview of RV Tauri stars

TheWISEview of RV Tauri stars

First detection of surface magnetic fields in post-AGB stars: the cases of U Monocerotis and R Scuti

The optically bright post-AGB population of the LMC

Contact Info

Product

Resources

About