Related papers: Chemical Evolution of Turbulent Multiphase Molecul…
Aims. We probe the effect of turbulent diffusion on the chemistry at the interface between a cold neutral medium (CNM) cloudlet and the warm neutral medium (WNM). Methods. We perform moving grid, multifluid, 1D, hydrodynamical simulations…
Using the adaptive mesh refinement code MG, we perform hydrodynamic simulations of the interaction of a shock with a molecular cloud evolving due to thermal instability and gravity. To explore the relative importance of these processes,…
We examine the formation of molecular gas behind shocks in atomic gas using a chemical/dynamical model, particular emphasis is given to constraints the chemistry places on the dynamical evolution. The most important result of this study is…
A physical model and two-dimensional numerical method for computing the evolution and spectra of protostellar clouds are described. The physical model is based on a system of magneto-gasdynamical equations, including ohmic and ambipolar…
The majority of hydrogen in the interstellar medium (ISM) is in atomic form. The transition from atoms to molecules and, in particular, the formation of the H$_2$ molecule, is a key step in cosmic structure formation en route to stars.…
A strong correlation between atmospheric pressure and molecular gas mass is found in central cluster galaxies and early-type galaxies. This trend and a similar trend with atmospheric gas density would naturally arise if the molecular clouds…
In our grid of multiphase chemical evolution models (Moll\'a & D\'iaz, 2005), star formation in the disk occurs in two steps: first, molecular gas forms, and then stars are created by cloud-cloud collisions or interactions of massive stars…
An overview is presented of the main properties of the interstellar medium. Evidence is summarized that the interstellar medium is highly turbulent, driven on different length scales by various energetic processes. Large-scale turbulence…
This review covers four current questions in the behavior of the atomic and molecular interstellar medium. These include whether the atomic gas originates primarily in cold streams or hot flows onto galaxies; what the filling factor of cold…
The chemistry of molecular clouds has been studied for decades, with an increasingly general and sophisticated treatment of the reactions involved. Yet the treatment of turbulent diffusion has remained extremely sketchy, assuming simple…
Star formation is one of the least understood processes in cosmic evolution. It is difficult to formulate a general theory for star formation in part because of the wide range of physical processes involved. The interstellar gas out of…
Aims. We study the effect of large scale dynamics on the molecular composition of the dense interstellar medium during the transition between diffuse to dense clouds. Methods. We followed the formation of dense clouds (on sub-parsec scales)…
We propose that inward, subsonic flows arise from the local dissipation of turbulent motions in molecular clouds. Such "turbulent cooling flows" may account for recent observations of spatially extended inward motions towards dense cores.…
The formation of compact dusty clouds in diffuse interstellar medium (ISM) has been recently proposed and studied by Tsytovich et al. (2014). In the present paper, an effect of the clouds on the rate of H$\to$H$_2$ transition in the ISM is…
Volcanic ash clouds often become multilayered and thin with distance from the vent. We explore one mechanism for development of this layered structure. We review data on the characteristics of turbulence layering in the free atmosphere, as…
We present the results from three dimensional hydrodynamical simulations of decaying high-speed turbulence in dense molecular clouds. We compare our results, which include a detailed cooling function, molecular hydrogen chemistry and a…
Formed at an early stage of gas-phase ion-molecule chemistry, hydrides -- molecules containing a heavy element covalently bonded to one or more hydrogen atoms -- play an important role in interstellar chemistry as they are the progenitors…
We review recent advances in the analytical and numerical modeling of the star formation rate in molecular clouds and discuss the available observational constraints. We focus on molecular clouds as the fundamental star formation sites,…
Molecular clouds, the birthplaces of stars in galaxies, form dynamically from the diffuse atomic gas of the interstellar medium (ISM). The ISM is also threaded by magnetic fields which have a large impact on its dynamics. In particular,…
Galaxies comprise intricate networks of interdependent processes which together govern their evolution. Central among these are the multiplicity of feedback channels, which remain incompletely understood. One outstanding problem is the…