Contents of: VI/111/./abstract/RIVISON_COLD.abs

The following document lists the file abstract/RIVISON_COLD.abs from catalogue VI/111.
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 A sub-millimetre excess has been detected in three symbiotic Miras
 (AGB + possible post-AGB binaries, two of which are also symbiotic
 novae). The excess is probably caused by emission from dust at lower
 temperatures than the 300-K dust shell which dominates the near- and
 mid-IR emission. The cold dust was predicted by earlier modelling of
 the mid- to far-IR IRAS data, and it could be evidence for a planetary
 nebula stage in the evolution of the Mira's hot companion.
 Alternatively, it might be a relic of repeated symbiotic nova
 outbursts, or it may have steady-state origins in the winds of the hot
 or cool components. Ground-based telescopes can only measure the
 continuum level at wavelengths longer than 350 microns, and IRAS gave
 only upper limits at 100 microns, so current estimates of dust masses
 and temperatures are very poorly constrained. Our observational
 objective is therefore to measure the mid- to far-IR continuum using
 PHT-C so that we can disentangle the IR and mm continuum processes
 (dust emission; optically thin free-free) and thus rigorously and
 quantitively test the reality of the cold dust components. Accurate
 photometry in this region is crucial in order to model the dust
 emission and thereby constrain the temperature and mass of the
 various dust shells.