STABILITY OF GAS CLOUDS IN GALACTIC NUCLEI: AN EXTENDED VIRIAL THEOREM
نویسندگان
چکیده
منابع مشابه
Molecular Gas in Galactic Nuclei
Dense molecular clouds are critical to the activity occurring in galactic nuclei. They are the active component from which starbursts arise, and this dense interstellar gas may be the fuel for AGNs. In both the nearby infrared bright galaxies (eg. M82, NGC 253, and IC342) and the ultralu-minous IRAS galaxies, high resolution millimeter line mapping has shown extremely high gas surface densities...
متن کاملGas and Dust in Ultraluminous Galactic Nuclei
Millimeter-wave interferometry has clearly shown the existence of enormous masses (10 9 ?10 10 M) of molecular gas concentrated in the nuclear regions (R <500 pc) of many luminous and ultraluminous infrared galaxies. In these systems, molecular gas is an obvious source of fuel for nuclear starbursts and active galactic nuclei (AGN). In several ultraluminous systems (e.g., Arp 220 and Mrk 231), ...
متن کاملVirial shocks in galactic haloes?
We investigate the conditions for the existence of an expanding virial shock in the gas falling within a spherical dark-matter halo. The shock relies on pressure support by the shock-heated gas behind it. When the radiative cooling is efficient compared to the infall rate the post-shock gas becomes unstable; it collapses inwards and cannot support the shock. We find for a monoatomic gas that th...
متن کاملDielectronic Recombination and Stability of Warm Gas in Active Galactic Nuclei
Understanding the thermal equilibrium (stability) curve may offer insights into the nature of the warm absorbers often found in active galactic nuclei. Its shape is determined by factors such as the spectrum of the ionizing continuum and the chemical composition of the gas. We find that the stability curves obtained under the same set of the above-mentioned physical factors, but using recently ...
متن کاملExtended Red Emission in High-Galactic Latitude Interstellar Clouds
Nearby interstellar clouds at high Galactic latitudes are ideal objects in which the interaction of interstellar dust with photons from the well-characterized interstellar radiation field can be studied. Scattering and UV-excited photoluminescence at optical wavelengths as well as thermal emission at midand far-infrared wavelengths are observable manifestations of such interactions. Here we rep...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 2016
ISSN: 1538-4357
DOI: 10.3847/0004-637x/819/2/138