Related papers: Interstellar Chemistry: Radiation, Dust and Metals
The abundances of gas and dust (solids and complex molecules) in the interstellar medium (ISM) as well as their composition and structures impact practically all of astrophysics. Fundamental processes from star formation to stellar winds to…
In the interstellar medium of the Milky Way, certain elements -- e.g., Mg, Si, Al, Ca, Ti, Fe -- reside predominantly in interstellar dust grains. These grains absorb, scatter, and emit electromagnetic radiation, heat the interstellar…
Dust is important for star formation because it is the crucial component that couples gas to stellar radiation fields, allowing radiation feedback to influence gas fragmentation and thus the stellar initial mass function (IMF). Variations…
Interstellar chemistry is important for galaxy formation, as it determines the rate at which gas can cool, and enables us to make predictions for observable spectroscopic lines from ions and molecules. We explore two central aspects of…
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…
Context. The presence of dust in the interstellar medium has profound consequences on the chemical composition of regions where stars are forming. Recent observations show that many species formed onto dust are populating the gas phase,…
We describe a phenomenological model for molecular hydrogen formation suited for applications in galaxy formation simulations, which includes on-equilibrium formation of molecular hydrogen on dust and approximate treatment of both its…
The interstellar medium is characterized by a rich and diverse chemistry. Many of its complex organic molecules are proposed to form through radical chemistry in icy grain mantles. Radicals form readily when interstellar ices (composed of…
Context. Interstellar dust particles, which represent 1% of the total mass, are recognized to be very powerful interstellar catalysts in star-forming regions. The presence of dust can have a strong impact on the chemical composition of…
In spite of accounting for only a small fraction of the mass of the Interstellar Medium (ISM), dust plays a primary role in many physical and chemical processes in the Universe. It is the main driver of extinction of radiation in the…
Comparison of the ISM properties of a wide range of metal-poor galaxies with normal metal-rich galaxies reveals striking differences. We find that the combination of the low dust abundance and the active star formation results in a very…
My thesis work aims to study the inter-relation between various physical and chemical conditions in a wide range of astrophysical environments. Our studied regions range from the super-hot regions (i.e., nebular, photon-dominated, or…
The model is constructed of the propagation of gamma-ray burst radiation through a dense molecular cloud. The main processes of the interaction of the radiation with the interstellar gas are taken into account in the simulations: the…
The Interstellar Medium (ISM) comprises gases at different temperatures and densities, including ionized, atomic, molecular species, and dust particles. The neutral ISM is dominated by neutral hydrogen and has ionization fractions up to 8%.…
Interstellar dust links the formation of the first stars to the rocky planet we inhabit by playing a pivotal role in the cooling and fragmentation of molecular clouds, and catalyzing the formation of water and organic molecules. Despite its…
Emission and absorption line observations of molecules in late-type stars are a vital component in our understanding of stellar evolution, dust formation and mass loss in these objects. The molecular composition of the gas in the…
High star-formation rate and active galactic nucleus' emission can significantly transform the interstellar medium. In ultra-luminous infrared galaxies, in which the star-formation rate reaches thousands of solar masses per year, the gas…
Dust grains coagulate into larger aggregates in dense gas. This changes their size distribution and possibly affects the thermal evolution of star-forming clouds. We here investigate dust coagulation in collapsing pre-stellar cores with…
The temperature of newly forming dust is controlled by the radiation field. As dust forms around stars, stellar transients, quasars or supernovae, the grains must grow through a regime where they are stochastically heated by individual…
The first part of this paper deals with the impact of nonsolar and - for late-type, dwarf, and high redshift galaxies - generally subsolar abundances on the interpretation of observational data for starburst galaxies. It points out the…