Related papers: Interstellar gas within $\sim 10$ pc of Sgr A$^*$
To investigate the interstellar medium (ISM) and Galactic cosmic rays (CRs) in the solar neighborhood, we analyzed ${\gamma}$-ray data by Fermi Large Area Telescope (LAT) for five nearby molecular cloud regions. Our data includes the…
The evidence for the presence of a concentration of dark matter at the Galactic center is now very compelling. There is no question that the stellar and gas kinematics within 0.01 pc is dominated by under-luminous matter in the form of…
(Abridged) We present fine structure and recombination lines observations of the ionized gas toward a sample of 18 sources located within 300 pc of the center of the Galaxy (GC). The fine structure lines from [NII] and [SIII] have been…
The cloud-scale density, velocity dispersion, and gravitational boundedness of the interstellar medium (ISM) vary within and among galaxies. In turbulent models, these properties play key roles in the ability of gas to form stars. New high…
Young massive stars in the central parsec of our Galaxy are best explained by star formation within at least one, and possibly two, massive self-gravitating gaseous discs. With help of numerical simulations, we here consider whether the…
We present a detailed study of molecular gas in the central 10pc of the Galaxy through spectral line observations of four rotation inversion transitions of NH3 made with the VLA. Updated line widths and NH3(1,1) opacities are presented, and…
We present new high resolution numerical simulations of the ISM in a central R ~32 parsecs region around a supermassive black hole at a galactic center. Three-dimensional hydrodynamic modeling of the ISM (Wada & Norman 2002) with the…
Galactic halo gas traces inflowing star formation fuel and feedback from a galaxy's disk and is therefore crucial to our understanding of galaxy evolution. In this review, we summarize the multi-wavelength observational properties and…
The formation of the massive young stars surrounding SgrA* is still an open question. In this paper, we simulate the infall of a turbulent molecular cloud towards the Galactic Center (GC). We adopt two different cloud masses (4.3x10^4 and…
We present a mass-temperature profile of gas within the central 10 kpc of a small sample of cool core clusters. The mass of the hottest gas phases, at 1.5 and 0.7 keV, is determined from X-ray spectra from the XMM Reflection Grating…
It is often assumed that the strong gravitational field of a super-massive black hole disrupts an adjacent molecular cloud preventing classical star formation in the deep potential well of the black hole. Yet, young stars have been observed…
Knowledge of the molecular component of the ISM is fundamental to understand star formation. The H2 component appears to dominate the gas mass in the inner parts of galaxies, while the HI component dominates in the outer parts. Observation…
We present new observations of the ultra-compact HII region G28.20-0.05 in 23 GHz continuum, and the NH3(1,1), NH3(2.2), and NH3(3,3) lines. To explain the complicated kinematics of the molecular gas, we propose a model consisting of two…
Observations of bright and variable "reflected" X-ray emission from molecular clouds located within inner hundred parsec of our Galaxy have demonstrated that the central supermassive black hole, Sgr A*, experienced short and powerful flares…
The compact radio source Sgr A* is coincident with a 4 million solar mass black hole at the dynamical center of the Galaxy and is surrounded by dense orbiting ionized and molecular gas. We present high resolution radio continuum images of…
In a previous paper, we calculated numerical hydrodynamic models of the interstellar medium in the Galaxy, which suggested that hot gas (T $\ge$ 3 $\times$ 10$^5$ K) has a filling factor near 50\% in the midplane (Rosen \& Bregman 1995, ApJ…
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…
A hot phase of the interstellar medium has now been detected and studied in several objects through its X-ray emission. A proper assessment of its characteristics is relevant for our understanding of several aspects of galaxy properties,…
Most of a galaxy's mass is located out to hundreds of kiloparsecs beyond its stellar component. This diffuse reservoir of gas, the circumgalactic medium (CGM), acts as the interface between a galaxy and the cosmic web that connects…
The interstellar medium (ISM) of galaxies very often contains a gas component that reaches the temperature of several million degrees, whose physical and chemical properties can be investigated through imaging and spectroscopy in the…