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Related papers: The axisymmetric envelopes of RS Cnc and EP Aqr

200 papers

We analyse continuum and molecular emission, observed with ALMA, from the dust-enshrouded intermediate-mass AGB star OH 30.1 -0.7. We find a secondary peak in the continuum maps, "feature B", separated by 4.6" from the AGB star, which…

Stars on the asymptotic giant branch (AGB) lose substantial amounts of matter, to the extent that they are important for the chemical evolution of, and dust production in, the universe. The mass loss is believed to increase gradually with…

Solar and Stellar Astrophysics · Physics 2015-10-28 Hans Olofsson , Per Bergman , Michael Lindqvist

A study is made of a sample of 58 dust-enshrouded Asymptotic Giant Branch (AGB) stars (including 2 possible post AGB stars), of which 27 are carbon-rich and 31 are oxygen-rich. These objects were originally identified by Jura & Kleinmann as…

Astrophysics · Physics 2009-11-06 Enrico A. Olivier , Patricia Whitelock , Fred Marang

(Abridged) We have used the VLA to search for neutral atomic hydrogen in the circumstellar envelopes of five AGB stars. We have detected HI 21-cm emission coincident in both position and velocity with the semi-regular variable RS Cnc. The…

Astrophysics · Physics 2008-11-26 Lynn D. Matthews , Mark J. Reid

We aim to study the main properties of a volume-limited unbiased sample of well-characterized semi-regular variables (SRs) in order to clarify important issues, such as the formation of axially symmetric planetary nebulae (PNe) from…

Solar and Stellar Astrophysics · Physics 2019-09-11 J. J. Díaz-Luis , J. Alcolea , V. Bujarrabal , M. Santander-García , A. Castro-Carrizo , M. Gómez-Garrido , J. -F. Desmurs

Over two decades ago, a prominent, mysterious emission band peaking at ~20.1 micrometer was serendipitously detected in four preplanetary nebulae (PPNe; also known as "protoplanetary nebulae"). So far, this spectral feature, designated as…

Solar and Stellar Astrophysics · Physics 2016-07-06 Ajay Mishra , Aigen Li , B. W. Jiang

Mass loss dominates the stellar evolution on the Asymptotic Giant Branch. The phase of highest mass-loss occurs during the last 1--10\% of the AGB and includes the so-called Miras and OH/IR stars. In this review I will discuss the…

Astrophysics · Physics 2009-10-22 Albert A. Zijlstra

We present the third and final part of a census of Asymptotic Giant Branch (AGB) stars in Local Group dwarf irregular galaxies. Papers I and II presented the results for WLM and IC 1613. Included here are Phoenix, LGS 3, DDO 210, Leo A,…

Astrophysics of Galaxies · Physics 2011-02-11 Martha L. Boyer , Evan D. Skillman , Jacco Th. van Loon , Robert D. Gehrz , Charles E. Woodward

The asymptotic giant branch (AGB) stars X Her and TX Psc have been imaged at 70 and 160 microns with the PACS instrument onboard the Herschel satellite, as part of the large MESS (Mass loss of Evolved StarS) Guaranteed Time Key Program. The…

The CO(J=3-2) emission from the CSE of the binary S-type AGB star W Aql has been observed at subarcsecond resolution using ALMA. The aim of this paper is to investigate the wind properties of the AGB star and to analyse how the known…

Our current insights into the circumstellar chemistry of asymptotic giant branch (AGB) stars are largely based on studies of carbon-rich stars and stars with high mass-loss rates. In order to expand the current molecular inventory of…

Solar and Stellar Astrophysics · Physics 2018-07-04 E. De Beck , H. Olofsson

Almost all stars in the 1-8 Msun range evolve through the Asymptotic Giant Branch (AGB), preplanetary nebula (PPN) and planetary nebula (PN) evolutionary phases. Most stars that leave the main sequence in a Hubble time will end their lives…

Bipolar planetary nebulae (PNe), as well as extreme elliptical PNe are formed through the influence of a stellar companion. But half of all PN progenitors are not influenced by any stellar companion, and, as I show here, are expected to…

Astrophysics · Physics 2016-01-27 Noam Soker

The symbiotic star R Aqr is part of a small sample of binary AGB stars observed with ALMA. The sample stars are: R Aqr, Mira, W Aql, and pi1 Gru. The sample covers a range in binary separation and wind properties, where R Aqr is the source…

Solar and Stellar Astrophysics · Physics 2018-08-15 S. Ramstedt , S. Mohamed , T. Olander , W. H. T. Vlemmings , T. Khouri , S. Liljegren

By cross-correlating the results of two recent large-scale surveys, the general properties of a well defined sample of semi-regular variable stars have been determined. ISOGAL mid-infrared photometry and MACHO lightcurves are assembled for…

The initial conditions for the mass loss during the asymptotic giant branch (AGB) phase are set in their extended atmospheres, where, among others, convection and pulsation driven shocks determine the physical conditions. High resolution…

Solar and Stellar Astrophysics · Physics 2019-06-19 W. H. T. Vlemmings , T. Khouri , H. Olofsson

The recent progress in high-spatial-resolution techniques, spanning wavelengths from the visual to the radio regime, is leading to new valuable insights into the complex dynamical atmospheres of Asymptotic Giant Branch (AGB) stars and their…

Solar and Stellar Astrophysics · Physics 2016-10-28 Susanne Höfner

I examine the implications of the recently found extrasolar planets on the planet-induced axisymmetrical mass loss model for the formation of elliptical planetary nebulae (PNs). This model, which was developed in several earlier papers by…

Astrophysics · Physics 2010-03-19 Noam Soker

This paper presents interferometric and single-dish CO observations along with HI data obtained for the oxygen-rich semi-regular variable RS Cnc, in order to probe its circumstellar environment at different scales. With the Plateau de Bure…

Solar and Stellar Astrophysics · Physics 2015-05-18 Yannick Libert , Jan Martin Winters , Thibaut Le Bertre , Eric Gérard , Lynn D. Matthews

I study some effects of aspherical mass loss during the last stages of the asymptotic giant branch (AGB) on the appearance of proto planetary nebulae (PNs) and young PNs. The aspherical mass loss can be small scale inhomogeneities, and/or…

Astrophysics · Physics 2009-10-31 Noam Soker