Related papers: Could the Galactic disk heating be due to Globular…
On the basis of the universal gas fraction in clusters of galaxies, we estimate that the effective thermal conductivity required to balance radiative cooling in the cores, where the gas temperature is 3-10keV, is about one tenth of the…
Halo clouds have been found about the three largest galaxies of the Local Group and in the halos of nearby spirals. This suggests they are a relatively generic feature of the galaxy evolution process and a source of fuel for galaxy disks.…
High-resolution imaging of some protoplanetary disks in scattered light reveals presence of the global spiral arms of significant amplitude, likely excited by massive planets or stellar companions. Assuming that these arms are density…
The evolution of the Milky Way disk, which contains most of the stars in the Galaxy, is affected by several phenomena. For example, the bar and the spiral arms of the Milky Way induce radial migration of stars and can trap or scatter stars…
We use FIRE simulations to study disk formation in z~0, Milky Way-mass galaxies, and conclude that a key ingredient for the formation of thin stellar disks is the ability for accreting gas to develop an aligned angular momentum distribution…
We investigate the effect of heating by luminosity sources in a simulation of clustered star formation. Our heating method involves a simplified continuum radiative transfer method that calculates the dust temperature. The gas temperature…
We investigate the dynamical effects of dark matter subhalos on the structure and evolution of a galactic disk, using semi-analytic method that includes approximated and empirical relations as achieved in detailed numerical simulations of…
A model is presented which calculates the gas temperature and chemistry in the surface layers of flaring circumstellar disks using a code developed for photon-dominated regions. Special attention is given to the influence of dust settling.…
The hot interstellar medium traces the stellar feedback and its role in regulating the eco-system of the Galaxy. I review recent progress in understanding the medium, based largely on X-ray absorption line spectroscopy, complemented by…
The radiative cooling timescales at the centers of hot atmospheres surrounding elliptical galaxies, groups, and clusters are much shorter than their ages. Therefore, hot atmospheres are expected to cool and to form stars. Cold gas and star…
We discuss the properties of an accretion disk around a star with parameters typical of classical T Tauri stars (CTTS), and with the average accretion rate for these disks. The disk is assumed steady and geometrically thin. The turbulent…
In recent years evidence has accumulated suggesting that the gas in galaxy clusters is heated by non-gravitational processes. Here we calculate the heating rates required to maintain a physically motived mass flow rate, in a sample of seven…
(Abridged) Interacting galaxies are well-known for their high star formation rates and rich star cluster populations, but the rapidly changing tidal field can also efficiently destroy clusters. We use numerical simulations of merging disc…
Cosmological simulations of galaxy clusters typically find that the weight of a cluster at a given radius is not balanced entirely by the thermal gas pressure of the hot ICM, with theoretical studies emphasizing the role of random turbulent…
We discuss the age of the stellar disks in the solar neighbourhood. After reviewing the various methods for age dating we discuss current estimates of the age of both the thin and the thick disk. We present preliminary results for…
Context: It is well known that the kinetic temperatures, Tkin, of the molecular clouds in the Galactic center region are higher than in typical disk clouds. However, the Tkin of the molecular complexes found at higher latitudes towards the…
Understanding our Galactic Center is easier with insights from nearby galactic nuclei. Both the star formation activity in nuclear gas disks, driven by bars and nuclear bars, and the fueling of low-luminosity AGN, followed by feedback of…
Open star clusters from the MWSC (Milky Way Star Clusters) catalogue have been used to determine the Galactic rotation parameters. The circular rotation velocity of the solar neighborhood around the Galactic center has been found from data…
Minor accretion events with mass ratio M_sat : M_host ~ 1:10 are common in the context of LCDM cosmology. We use high-resolution simulations of Galaxy-analogue systems to show that these mergers can dynamically eject disk stars into a…
In conventional models of galactic and cluster cooling flows widespread cooling (mass dropout) is assumed to avoid accumulation of unacceptably large central masses. However, recent XMM observations have failed to find spectral evidence for…