Analysis of ISO SWS01 spectra of S stars

PS(陈培生), Chen; JC, Wang; He, J.-J.

doi:10.1051/0004-6361:20065048

Cited by 12 publications

(12 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…S stars tend to have low mass-loss rate, implying less efficient dust formation. However, Yang et al (2007) finds that some S stars show silicate dust emission features.…”

Section: (C) S Starsmentioning

confidence: 99%

A Catalog of Agb Stars in Iras PSC

Suh

Kwon²

2009

Journal of The Korean Astronomical Society

View full text Add to dashboard Cite

We make a new catalog of AGB stars in our Galaxy from the sources listed in the Infrared Astronomical Satellite (IRAS) point source catalog (PSC) compiling the lists of previous works with verifying processes. We verify the class identification of AGB stars into oxygen-rich and carbon-rich stars using the information from recent investigations. For the large sample of AGB stars, we present infrared two-color diagrams from the observations at near infrared bands and IRAS PSC. On the two-color diagrams, we plot the tracks of theoretical radiative transfer model results with increasing dust shell optical depths. Comparing the observations with the theoretical tracks, we discuss the meaning of the infrared two-color diagrams.

show abstract

“…S stars tend to have low mass-loss rate, implying less efficient dust formation. However, Yang et al (2007) finds that some S stars show silicate dust emission features.…”

Section: (C) S Starsmentioning

confidence: 99%

A Catalog of Agb Stars in Iras PSC

Suh

Kwon²

2009

Journal of The Korean Astronomical Society

View full text Add to dashboard Cite

show abstract

“…Both emissions result in a peak position (for the blended silicate plus alumina bands) of about 10.5 μm (Yang et al 2007). …”

Section: Introductionmentioning

confidence: 99%

Large-scale environments of binary AGB stars probed by Herschel

Mayer¹,

Jorissen²,

Kerschbaum³

et al. 2012

A&A

View full text Add to dashboard Cite

The Mass loss of Evolved StarS (MESS) sample offers a selection of 78 asymptotic giant branch (AGB) stars and red supergiants (RSGs) observed with the PACS photometer on-board Herschel at 70 μm and 160 μm. For most of these objects, the dusty AGB wind is not spherically symmetric and the wind shape can be subdivided into four classes. In the present paper we concentrate on the influence of a companion on the morphology of the stellar wind. Literature was searched to find binaries in the MESS sample, which were subsequently linked to their wind-morphology class to assert that the binaries are not distributed equally among the classes. In the second part of the paper we concentrate on the circumstellar environment of the two prominent objects R Aqr and W Aql. Each shows a characteristic signature of a companion interaction with the stellar wind. For the symbiotic star R Aqr, PACS revealed two perfectly opposing arms that in part reflect the previously observed ring-shaped nebula in the optical. However, from the far-IR there is evidence that the emitting region is elliptical rather than circular. The outline of the wind of W Aql seems to follow a large Archimedean spiral formed by the orbit of the companion but also shows strong indications of an interaction with the interstellar medium. We investigated the nature of the companion of W Aql and found that the magnitude of the orbital period supports the size of the spiral outline.

show abstract

“…Nevertheless, due to shock-induced non-equilibrium chemistry effects, S-type stars could display carbon-rich molecules (Cherchneff 2006). Recent studies of ISO/SWS spectra of S-type AGB stars indeed show the presence of molecules like HCN and C 2 H 2 (Yang et al 2007;.…”

Section: Introductionmentioning

confidence: 99%

When an old star smolders

Smolders¹,

Acke²,

Verhoelst³

et al. 2010

A&A

View full text Add to dashboard Cite

Polycyclic aromatic hydrocarbons (PAHs) produce characteristic infrared emission bands that have been observed in a wide range of astrophysical environments, where carbonaceous material is subjected to ultraviolet (UV) radiation. Although PAHs are expected to form in carbon-rich AGB stars, they have up to now only been observed in binary systems where a hot companion provides a hard radiation field. In this letter, we present low-resolution infrared spectra of four S-type AGB stars, selected from a sample of 90 S-type AGB stars observed with the infrared spectrograph aboard the Spitzer satellite. The spectra of these four stars show the typical infrared features of PAH molecules. We confirm the correlation between the temperature of the central star and the centroid wavelength of the 7.9 μm feature, present in a wide variety of stars spanning a temperature range from 3000 to 12 000 K. Three of four sources presented in this paper extend this relation towards lower temperatures. We argue that the mixture of hydrocarbons we see in these S-stars has a rich aliphatic component. The fourth star, BZ CMa, deviates from this correlation. Based on the similarity with the evolved binary TU Tau, we predict that BZ CMa has a hot companion as well.

show abstract

Analysis of ISO SWS01 spectra of S stars

Cited by 12 publications

References 31 publications

A Catalog of Agb Stars in Iras PSC

A Catalog of Agb Stars in Iras PSC

Large-scale environments of binary AGB stars probed by Herschel

When an old star smolders

Contact Info

Product

Resources

About