Related papers: Grains in Photo-Ionized Environments
Observations of gaseous complex organic molecules (COMs) in cold starless and prestellar cloud cores require efficient desorption of the COMs and their parent species from icy mantles on interstellar grains. With a simple astrochemical…
The degree of porosity in interstellar dust-grain material is poorly defined, although recent work has suggested that the grains could be highly porous. Aside from influencing the optical properties of the dust, porosity has the potential…
Thermal dust polarization is a powerful tool to probe magnetic fields ($\textbf{B}$) and grain properties. However, a systematic study of the dependence of dust polarization on grain properties in protostellar environments is not yet…
Segregation to grain boundaries affects their cohesion, corrosion and embrittlement and plays a critical role in heterogeneous nucleation. In order to quantitatively study segregation and phase separation at grain boundaries, we derive a…
The life-cycle of cosmic dust grains is far from being understood and the origin and evolution of interstellar medium (ISM) grains is still under debate. In the ISM, the cosmic dust destruction rate is faster than the production rate by…
Gas-phase chemistry at extreme conditions (low densities and temperatures) is difficult, so the presence of interstellar grains is especially important for the synthesis of molecules that cannot form in the gas phase. Interstellar grains…
By radiation transfer models with a realistic power spectra of the projected density distributions, we show that the optical properties of grains are poorly constrained by observations of reflection nebulae. The ISM is known to be…
The reionization of the second electron of helium (HeII) leaves important imprints on the thermal and ionization state of the intergalactic medium (IGM). Observational evidence suggests that HeII reionization ended at $z \simeq 3$ due to…
Grains are widely assumed to be characterized by a single temperature -- derived either from the configurational entropy, or employing the kinetic theory. Yet granular media do have two temperatures, $T_g$ and $T$, pertaining to the grains…
Context. Dust grains in circumstellar envelopes are likely to have a spread-out temperature distribution. Aims. To investigate how trends in temperature distribution between small and large grains affect the hot corino chemistry of complex…
In order to interpret observations influenced by dust and to perform detailed modeling of the observable characteristics of dust-producing or dust-containing objects, knowledge of the micro-physical properties of relevant dust species are…
We recently questioned the treatment of a dust particle as a perfect absorber for electrons and ions and proposed a surface model for the charge of a dust particle in a quiescent plasma which combines the microscopic physics at the grain…
Granular materials are involved in most industrial and environmental processes, as well as many civil engineering applications. Although significant advances have been made in understanding the statics and dynamics of cohesionless grains…
Grain boundaries (GB) profoundly influence the electrical properties of polycrystalline ionic solids. Yet, precise control of their transport characteristics has remained elusive, thereby limiting the performance of solid-state…
We present an efficient heating/cooling method coupled with chemistry and ultraviolet (UV) radiative transfer, which can be applied to numerical simulations of the interstellar medium (ISM). We follow the time-dependent evolution of…
C-fractionation has been studied from a theoretical point of view with different models of time-dependent chemistry, including both isotope-selective photodissociation and low-temperature isotopic exchange reactions. Recent chemical models…
We carry out Monte-Carlo simulation to study deuterium enrichment of interstellar grain mantles under various physical conditions. Based on the physical properties, various types of clouds are considered. We find that in diffuse cloud…
We present interstellar absorption line measurements of the ions S III and Al III towards six stars using archival Goddard High Resolution Spectrograph data. The ions Al III and S III trace heavily depleted and non-depleted elements,…
(abridged) We aim to predict the most important parameters for grain-grain collision outcomes for models of interstellar grain population evolution on astrophysical scales: the threshold velocity above which colliding grains shatter, the…
A new, more comprehensive model of gas-grain chemistry in hot molecular cores is presented, in which nondiffusive reaction processes on dust-grain surfaces and in ice mantles are implemented alongside traditional diffusive surface/bulk-ice…