engleski

Modelling of Circumstellar Dust around Symbiotic Miras in Infrared

We determined circumstellar dust properties and modelled inner dust regions around the cool Mira components in a sample of symbiotic Miras which showed obscuration events during the observed time intervals. The published JHKL magnitudes of o Ceti, RX Pup, KM Vel, V366 Car, V835 Cen, RR Tel, R Aqr have been collected. In order to follow the evolution of their colours in time, their light curves were corrected by removing the Mira pulsations. Using the simultaneously available JHKL magnitudes and ISO spectra for different time intervals we obtained SEDs for RR Tel which cover the near- and mid-infrared spectral region in the periods with and without obscuration. The same procedure has been applied to other stars from the sample. The DUSTY code was used to solve the radiative transfer in order to determine the dust temperature and its properties in each particular case under the assumption of the spherical temperature distribution of the dust in the close neighbourhood around the Mira component. Dust temperature, grain size, density distribution and optical depth during intervals with and without obscuration have been obtained. Using the reconstructed SEDs in the infrared, we were able to model the chemical dust composition. Special attention was given to model circumstellar envelope around RR Tel.

binary stars; symbiotic stars; radiative transfer; circumstellar dust; infrared

Rad je objavljen i u Knjizi sažetaka ; str. 38-38. Rad je kao poster prezentiran i na skupu XXVIIth General Assembly of The International Astronomical Union, održanom od 03.-14.08.2009.g., Rio de Janeiro, Brazil ; objavljen u Knjizi sažetaka, str. 397-397.