Contents of: VI/111/./abstract/SDEGUCHI_DEGUCHI1.abs

The following document lists the file abstract/SDEGUCHI_DEGUCHI1.abs from catalogue VI/111.
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Some evolved stars exhibit peculiar features in their IRAS Low
Resolution Spectra. The features are difficult to be assigned to any
known atomic/molecular bands or a normal composite of grains. The
peculiarities in the spectra can be classified into three types:(1)
very sharp peaks at wavelengths which do not correspond with any known
atomic or molecular bands, (2) a broad but apparently band-like
feature at special wavelengths, (3) a very broad flat feature with a
peculiar inclination in the whole spectra betweeen 7-25 micron. One
possible interpretation of these strange spectra is that they are
due to a malfunction (or noise) of the IRAS low resolution
spectrometer at the time of data acquisition. The other interpretation
is that the infrared source consists of two objects closely laying, and
the spectra of the different types are symbiotic. The third
possibility is that these are true anomaly of the stellar spectra
due to unknown molecular or dust band emission/absorption, or atomic
lines in unusual excitational states. First, we would like to confirm
the peculiar features which were observed before with IRAS. Then,
we wish to identify and search new features. They may be a true anomaly
of the spectra, which may originate from unusually intense atomic
or molecular lines (such as infrared lasers or Raman scattering),
or from the emission band of unknown solid in the
circumstellar envelope. One of the aims of this proposal is to find
previously unknown, unusually strong lines of atoms or molecules
in the mid-infrared wavelength range, and to use them as future probes
of circumstellar envelopes.