The transition from AGB to post-AGB evolution as observed by AKARI and Spitzer
| dc.creator | Engels, D. | |
| dc.creator | García-Lario, P. | |
| dc.creator | Bunzel, F. | |
| dc.creator | García-Hernández, D. A. | |
| dc.creator | Perea-Calderón, J. V. | |
| dc.date | 2009-04-27 | |
| dc.date.accessioned | 2026-07-07T13:08:49Z | |
| dc.date.available | 2026-07-07T13:08:49Z | |
| dc.description | The AKARI and Spitzer satellites provided an unique opportunity to observe a variety of stars, which are considered as departing from the Asymptotic Giant Branch (AGB) and have started their post-AGB evolution recently. Most of these stars are absent optically and are bright in the mid-IR wavelength range. Spectra of close to 200 objects have been obtained. For all of them the 1-60 micron spectral energy distribution has been constructed using photometric data from various surveys. We report here on the results of Spitzer observations of 88 IRAS selected post-AGB candidates and discuss them in comparison to the results of the AKARI observations of post-AGB candidates reported elsewhere in these proceedings. The dust compositions can be divided broadly in oxygen- and carbon-rich types, but a variety of intermediate types have been found. Among the oxygen-rich stars amorphous dust prevails, but a few sources show emission features from crystalline dust. The spectra from carbon-rich shells may be completely featureless, may show emission features from PAHs or a molecular absorption line from C2H2. We found also sources with a neon emission line at 12.8 micron. More than a third of all sources show a near-infrared excess at < 5 micron and almost all of them show evidence of C-rich dust in their shells. We postulate that the emerging post-AGB wind after the end of AGB evolution contains always carbon-rich dust irrespective of the chemistry of the former AGB star. | |
| dc.description | 6 pages, 4 figures, conference paper | |
| dc.identifier | https://arxiv.org/abs/0904.3958 | |
| dc.identifier | http://arxiv.org/abs/0904.3958 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/228539 | |
| dc.subject | Solar and Stellar Astrophysics | |
| dc.title | The transition from AGB to post-AGB evolution as observed by AKARI and Spitzer | |
| dc.type | text |