Towards the Identification of the Circumstellar Dust Feature at 13mu
Abstract
The IRAS LRS data of many O-rich evolved stars show an emission feature at 13 micron. Al_2O_3 has been proposed in the literature as the carrier of this band. We compared the average profile from 51 objects with profiles computed from laboratory data of amorphous and crystalline Al_2O_3. We found that (1) the 13 micron band could not be fitted by amorphous Al_2O_3, (2) the 13 micron band could probably be fitted by a suitable distribution of spherical and ellipsoidal grains of crystalline alpha-Al_2O_3, and (3) the strength of the 10 micron silicate feature correlates well with the strength of the 13 micron feature making silicate a possible carrier of this band.
- Publication:
-
Commmunications of the Konkoly Observatory Hungary
- Pub Date:
- January 1997
- Bibcode:
- 1997CoKon.100..323K