Astronomy and Astrophysics – Astrophysics
Scientific paper
2007-03-25
Astron.J.134:205-213,2007
Astronomy and Astrophysics
Astrophysics
24 pages, 6 figures, 5 tables - to be published in AJ
Scientific paper
10.1086/518406
We investigate the IR spectral features of a sample of D-type symbiotic stars. Analyzing unexploited ISO-SWS data, deriving the basic observational parameters of dust bands and comparing them with respect to those observed in other astronomical sources, we try to highlight the effect of environment on grain chemistry and physic. We find strong amorphous silicate emission bands at 10 micron and 18 micron in a large fraction of the sample. The analysis of the 10 micron band, along with a direct comparison with several astronomical sources, reveals that silicate dust in symbiotic stars shows features between the characteristic circumstellar environments and the interstellar medium. This indicates an increasing reprocessing of grains in relation to specific symbiotic behavior of the objects. A correlation between the central wavelength of the 10 and 18 micron dust bands is found. By the modeling of IR spectral lines we investigate also dust grains conditions within the shocked nebulae. Both the unusual depletion values and the high sputtering efficiency might be explained by the formation of SiO moleculae, which are known to be a very reliable shock tracer. We conclude that the signature of dust chemical disturbance due to symbiotic activity should be looked for in the outer, circumbinary, expanding shells where the environmental conditions for grain processing might be achieved. Symbiotic stars are thus attractive targets for new mid-infrared and mm observations.
Angeloni Rodolfo
Ciroi Stefano
Contini Marcella
Rafanelli Piero
No associations
LandOfFree
Silicates in D-type symbiotic stars: an ISO overview does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Silicates in D-type symbiotic stars: an ISO overview, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Silicates in D-type symbiotic stars: an ISO overview will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-702425