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Post-AGB Stars as Tracers of AGB Nucleosynthesis: An Update
Universe, 2022 The chemical evolution of galaxies is governed by the chemical yields from stars, and here we focus on the important contributions from asymptotic giant branch (AGB) stars. AGB nucleosynthesis is, however, still riddled with complexities. Observations from post-asymptotic giant branch (post-AGB) stars serve as exquisite tools to quantify and understand
D Kamath +2 more
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Infrared spectroscopic study of a selection of AGB and post-AGB stars [PDF]
Monthly Notices of the Royal Astronomical Society, 2008 We present here near-infrared spectroscopy in the H and K bands of a selection of nearly 80 stars that belong to various AGB types, namely S type, M type and SR type. This sample also includes 16 Post-AGB (PAGB) stars. From these spectra, we seek correlations between the equivalent widths of some important spectral signatures and the infrared colors ...
Raman, V. Venkata, Anandarao, B. G.
exaly +3 more sources
Symposium - International Astronomical Union, 1997 Low and intermediate mass stars leave the Asymptotic Giant Branch (AGB) when the mass in their H-rich envelope is less than about 0.01 M⊙, and the high mass loss drops several orders of magnitude. The central star rapidly evolves to the left part of the HR diagram along a track of constant luminosity (e.g. Schönberner 1983).
van Winckel, H. +2 more
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Post-AGB stars as testbeds of nucleosynthesis in AGB stars [PDF]
Astronomy & Astrophysics, 2006 We construct a data base of 125 post-AGB objects (including R CrB and extreme helium stars) with published photospheric parameters (effective temperature and gravity) and chemical composition. We estimate the masses of the post-AGB stars by comparing their position in the (log Teff, log g) plane with theoretical evolutionary tracks of different masses.
Stasinska, Grazyna +3 more
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Crystalline silicates in AGB and post-AGB stars [PDF]
Symposium - International Astronomical Union, 1999 We discuss ISO spectroscopy of oxygen-rich dust shells surrounding evolved stars. The dust that condenses in the outflows of stars on the Asymptotic Giant Branch consists mainly of amorphous silicates and simple oxides. For high mass loss rates, crystalline silicates begin to appear at modest abundance. These crystalline silicates are cold and Fe-poor.
Waters, LBFM, Molster, FJ
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The Spectral Evolution of Post-AGB Stars [PDF]
Symposium - International Astronomical Union, 1997 We have performed a parameter study of the spectral evolution of a typical post-AGB star with particular emphasis on the evolution of the IRAS colours. The models are based on the latest evolutionary tracks by Blöcker (1995, A&A 297, 727 and A&A 299, 755), which are used to define the evolutionary rate and the mass loss history of the central ...
van Hoof, P.A.M. +2 more
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Properties of Post-AGB Stars [PDF]
Proceedings of the International Astronomical Union, 2006 Multi-wavelength analyses of an increasing number of post-AGB stars reveal that they constitute a more inhomogeneous population of stars than previously thought. The new data collected in the last few years allow us to study these sources with unprecedented spatial resolution and to extend our spectroscopic knowledge in a systematic way to the infrared
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Ubvri Polarization Measurements of Post AGB Stars [PDF]
Symposium - International Astronomical Union, 1993 UBVRI polarization measurements of 25 post AGB stars with circumstellar dust shells (CDSs) were made. Most of them show A, F, G, K supergiant type spectra. IRAS data of these stars show evidence for the presence cool detached circumstellar dust envelopes. Some of these stars also have warm dust shells. Many show significant polarization.
M. Parthasarathy, S. K. Jain
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Chemical composition of post‐AGB star candidates [PDF]
Astronomische Nachrichten, 2018 We present a high‐resolution detailed abundance analysis for a sample of six post‐Asymptotic Giant Branch (AGB) candidate stars, five of them had not been studied spectroscopically in the optical region. All the analyzed objects are IRAS sources identified as possible post‐AGB on the two‐color Infrared Astronomical Satellite (IRAS) diagram.
Molina, R. E. +2 more
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Cerium: The lithium substitute in post-AGB stars [PDF]
Astronomy & Astrophysics, 2002 In this letter we present an alternative identification for the line detected in the spectra of s-process enriched low-mass post-AGB stars around 6708A and which was interpreted in the literature as due to Li. Newly released line lists of lanthanide species reveal, however, the likely identification of the line to be due to a CeII transition.
Reyniers, M. +3 more
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