Naslov
Properties of circumstellar dust in symbiotic Miras

Autori
Jurkić, Tomislav ; Kotnik-Karuza, Dubravka

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Abstract book of Workshop on symbiotic stars, binary post-AGB and related objects / Mikolajewska, Joanna ; Otulakowska-Hypka, Magdalena ; Siodmiak, Natasza ; Szczerba, Ryszard - Varšava : N. Copernicus Astronomical Center, Polish Academy of Science, 2013

Skup
Workshop on symbiotic stars, binary post-AGB and related objects

Mjesto i datum
Wierzba, Poljska, 18.08.2013. - 23.08.2013

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
binaries: symbiotic; circumstellar matter; radiative transfer; stars: AGB and post-AGB; infrared: stars

Sažetak
Symbiotic binaries with a cool Mira component are characterized by the presence of substantial dust and by the appearance of near-IR obscuration intervals. To understand such symbiotic Miras, their evolution, mutual interactions between the components and circumstellar matter, the influence of stellar winds and mass transfer mechanism, it is essential to determine the properties of circumstellar dust and their temporal evolution. We have determined the physical properties of circumstellar dust in different obscuration intervals and in different stages after the nova outburst, with special emphasis on two probably best observed symbiotic Miras, HM Sge and RR Tel. Publicly available near- and mid-IR observations were used including infrared spectra from IRAS and ISO, as well as long-term ground-based photometry from SAAO and Crimean observatory. The spectral energy distribution in the near- and mid-IR spectral range (1-15 microns) was obtained for epochs with different obscuration levels and stages of post-nova evolution. The DUSTY code was used to solve the radiative transfer through the dust and to determine the circumstellar dust properties of the inner dust regions around the Mira component. Dust temperature, maximum grain size, dust density distribution, mass-loss rate, terminal wind velocity and optical depth have been determined. We have also performed an analysis of pulsations in epochs with and without pronounced near-IR obscuration. These obscuration intervals can be fully understood by increased mass loss and by condensation of new amounts of dust near the sublimation radius which leads to the observed increased optical depth.

Izvorni jezik
Engleski

Znanstvena područja
Fizika

POVEZANOST RADA