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We have discovered unresolved narrow emission lines in the ISO SWS
spectra of a number of oxygen-rich mira variables in our guaranteed
time proposal. These lines are only detected in the spectrum of stars
that show the 13um dust emission feature which has been attributed to
some form of aluminum oxide.
The presence of aluminum oxide has been associated with the occurrence
of shocks in the mira atmosphere. Thus, the unidentified lines
could possibly due to atomic or ionic lines in the shocked gas. In order
to be able to further study these lines and to resolve and identify
them, we need high resolution measurements. This data may enable us to
take a major step forward in our understanding of dust formation in
shocked extended mira atmospheres.
OBSID  : TDEJONG
PROPID : AGBSTAR1