Gas and dust spectra of the D' type symbiotic star HD330036

Abstract

We present a comprehensive and self-consistent modelling of the D' type symbiotic star (SS) HD330036 from radio to UV. Within a colliding-wind scenario, we analyse the continuum, line and dust spectra by means of SUMA, a code that simulates the physical conditions of an emitting gaseous cloud under the coupled effect of ionization from an external radiation source and shocks. We find that the UV lines are emitted from high density gas between the stars downstream of the reverse shock, while the optical lines are emitted downstream of the shock propagating outwards the system. As regards with the continuum SED, three shells are identified in the IR, at 850K, 320 K and 200 K with radii r = 2.8 10^13 cm, 4 10^14$ cm, and 10^15 cm, respectively, adopting a distance to Earth d=2.3 kpc: interestingly, all these shells appear to be circumbinary. The analysis of the unexploited ISO-SWS spectrum reveals that both PAHs and crystalline silicates coexist in HD330036, with PAHs associated to the internal shell at 850 K, and crystalline silicates stored into the cool shells at 320 K and 200 K. Strong evidence that crystalline silicates are shaped in a disk-like structure is derived on the basis of the relative band strengths. Finally, we suggest that shocks can be a reliable mechanism in activating the annealing and the consequent crystallization processes. We show that a consistent interpretation of gas and dust spectra emitted by SS can be obtained by models which accounts for the coupled effect of the photoionizing flux and of shocks. The VLTI/MIDI proposal recently accepted by ESO aims to verify and better constrain some of our results by means of IR interferometric observations.

arXiv comment11 pages, 5 figures, accepted for publication in A&A on 10th May 2007

References in corpus (23)

• The rich 6 to 9 um spectrum of interstellar PAHs
• An empirical formula for the mass-loss rates of dust-enshrouded red supergiants and oxygen-rich Asymptotic Giant Branch stars
• A catalogue of symbiotic stars
• The CH out-of-plane bending modes of PAH molecules in astrophysical environments
• The profiles of the 3 to 12 $\mu$m PAH features
• Crystalline silicate dust around evolved stars II. The crystalline silicate complexes
• Annealing of Silicate Dust by Nebular Shocks at 10 AU
• Crystalline silicate dust around evolved stars III. A correlations study of crystalline silicate features
• Crystalline silicate dust around evolved stars I. The sample stars
• Crystallinity versus mass-loss rate in Asymptotic Giant Branch stars
• Planetary nebula or symbiotic Mira? Near infrared colours mark the difference
• The symbiotic star CH Cygni. I. Non-thermal bipolar jets
• PAHs and crystalline silicates in the post-AGB star IRAS 16279-4757
• The Stellar Parameters and Evolutionary State of the Primary in the d'-Symbiotic System StH\alpha190
• The Infrared Continuum of Active Galaxies
• Magnetic Activity of the Cool Companion in Symbiotic Systems
• Discovery of a bipolar and highly variable mass outflow from the symbiotic binary StHa 190
• Modeling RR Tel through the Evolution of the Spectra
• Rotational velocities of the giants in symbiotic stars: I. D'-type symbiotics
• An analysis of the emission line spectra of AG Pegasi between phases 7.34 and 9.44
• R Aquarii spectra revisited by SUMA
• Silicates in D-type symbiotic stars: an ISO overview
• Internal and external shock fronts in He2-104

Cited by in corpus (8)

• A census of symbiotic stars in the 2MASS, WISE and Gaia surveys
• Catalogue of central stars of planetary nebulae: Expanded edition
• Herschel/PACS observations of the 69 $\mu m$ band of crystalline olivine around evolved stars
• The spectral energy distribution of D-type symbiotic stars: the role of dust shells
• Shock fronts in the symbiotic system BI Crucis
• The symbiotic star CH Cygni. II. The broad Ly alpha emission line explained by shocks
• The symbiotic system AG Draconis. Soft X-ray bremsstrahlung from the nebulae
• Studies of a possible new Herbig Ae/Be star in the open cluster NGC 7380