Related papers: The essential elements of dust evolution: a-C(:H) …
We present new models for the evolution of stars with mass in the range 1Msun < M < 7.5Msun, followed from the pre-main-sequence through the asymptotic giant branch phase. The metallicity adopted is $Z=3*10^{-4} (which, with an…
% context {Nano-diamonds are an enticing and enigmatic dust component yet their origin is still unclear. They have been unequivocally detected in only a few astronomical objects, yet they are the most abundant of the pre-solar grains, both…
Infrared carbon stars without visible counterparts are generally known as extreme carbon stars. We have selected a subset of these stars with absorption features in the 10-13 $\mu$m range, which has been tentatively attributed to silicon…
Using a radiative transfer code (DUSTY) parameters of the circumstellar dust shells of 15 hot post-AGB stars have been derived. Combining the optical, near and far-infrared (ISO, IRAS) data of the stars, we have reconstructed their spectral…
We present a numerical tool Shiva designed to simulate the dust destruction in warm neutral, warm ionized, and hot ionized media under the influence of photo-processing, sputtering, and shattering. The tool is designed primarily to study…
Dust coagulation in protoplanetary disks is not straightforward and is subject to several slow-down mechanisms, such as bouncing, fragmentation and radial drift to the star. Furthermore, dust grains in UV-shielded disk regions are…
We have obtained new STIS/HST spectra to search for structure in the ultraviolet interstellar extinction curve, with particular emphasis on a search for absorption features produced by polycyclic aromatic hydrocarbons (PAHs). The presence…
We formulate and calculate the evolution of dust in a galaxy focusing on the distinction among various dust components -- silicate, aromatic carbon, and non-aromatic carbon. We treat the galaxy as a one-zone object and adopt the evolution…
A sizable fraction of the heavy elements synthesized by stars in galaxies condenses into sub-micron-sized solid-state particles, known as dust grains. Dust produces a wavelength-dependent attenuation, $A_\lambda$, of the galaxy emission,…
The mass density of dust particles that form from asteroids and comets in the interplanetary medium of the solar system is, near 1 AU, comparable to the mass density of the solar wind. It is mainly contained in particles of micrometer size…
We investigate spatial distributions of specific dust components in the circumstellar shells of a proto-planetary nebula candidate, HD 179821, and a planetary nebula, BD$+30^{\circ}$3639, by means of spectral imaging. With high-resolution…
With the help of model calculations we aim at reproducing the observational photometric findings for a large sample of well-characterised galactic C-type Mira variables losing mass at different rates. We used dynamic model atmospheres,…
Observations conducted using the Atacama Large Millimeter/submillimeter Array on the protoplanetary disk around TW Hya show the nitrogen fractionation of HCN molecules in HC$^{14}$N/HC$^{15}$N $\sim$120 at a radius of $\sim$20 AU. In this…
We upgraded the chemical network from the UMIST Database for Astrochemistry 2006 to include isotopes such as ^{13}C and ^{18}O. This includes all corresponding isotopologues, their chemical reactions and the properly scaled reaction rate…
For amorphous carbon several laboratory extinction data are available, which show quite a wide range of differences due to the structural complexity of this material. We have calculated self-consistent dynamic models of circumstellar…
A broad array of interstellar absorption features that appear in the ultraviolet spectra of bright sources allows us to measure the abundances and ionization states of many important heavy elements that exist as free atoms in the…
Models of astrophysical dust are key to understand several physical processes, from the role of dust grains as cooling agents in the ISM to their evolution in dense circumstellar disks, explaining the occurrence of planetary systems around…
Carbon is an essential element for a habitable world. Inner (r < 3 au) disk planetary carbon compositions are strongly influenced by supply and survival of carbonaceous solids. Here we trace the journey of carbon from the interstellar…
Mid-infrared spectroscopy of dense illuminated ridges (or photodissociation regions, PDRs) suggests dust evolution. Such evolution must be reflected in the gas physical properties through processes like photo-electric heating or H_2…
We discuss the different dust components of a protoplanetary disk with a special emphasis on grain composition, size and structure. The paper will highlight the role dust grains play in protoplanetary disks, as well as observational results…