we propose to study the mass loss phenomenon during the final phases of the asymptotic giant branch (agb) evolution. to resolve the mass loss history over the longest possible look-back times we need to map the cold (20-30 k) and faint outer parts of the dust shells with the best possible sensitivity. this cannot be done from the ground; the iras data base and the kuiper airborne observatory do not have sufficient sensitivity. for our purposes isophot-c is the instrument of choice. we will make very deep images at 90 and 160 microns of the extended dust shells around obscured agb stars and young post-agb stars using oversampled raster maps (aot pht32). for sources at a typical distance of 0.5 kpc, the spatial resolution and sensitivity will be sufficient to study in detail the history of the agb mass loss with a time resolution of 3,000 yr and a look-back time of 1e5 yr (virgul1-2 thermal pulse cycles). in addition, the integrated dust distributions of the shells will provide much improved limits on their dust masses, a property which is much debated and poorly known. finally, the square maps will enable us to observe the dust shell morphology on the largest scales.
Instrument
PHT32
Temporal Coverage
1996-05-04T09:13:16Z/1997-04-10T20:44:48Z
Version
1.0
Mission Description
The Infrared Space Observatory (ISO) was the worlds first true orbiting infrared observatory. Equipped with four highly-sophisticated and versatile scientific instruments, it was launched by Ariane in November 1995 and provided astronomers world-wide with a facility of unprecedented sensitivity and capabilities for a detailed exploration of the Universe at infrared wavelengths.
European Space Agency, VAN DER VEEN et al., 1999, 'IMAGING OF DUST SHELLS AROUND AGB AND POST-AGB STARS openParPART 2closePar', 1.0, European Space Agency, https://doi.org/10.5270/esa-c6335sm
