Interstellar Media in the Magellanic Clouds and other Local Group Dwarf Galaxies
نویسنده
چکیده
I review the properties of the interstellar medium in the Magellanic Clouds and Local Group dwarf galaxies. The more massive, star-forming galaxies show a complex, multi-phase ISM full of shells and holes ranging from very cold phases (a few 10 K) to extremely hot gas (> 10 K). In environments with high UV radiation fields the formation of molecular gas is suppressed, while in dwarfs with low UV fields molecular gas can form at lower than typical Galactic column densities. There is evidence of ongoing interactions, gas accretion, and stripping of gas in the Local Group dwarfs. Some dwarf galaxies appear to be in various stages of transition from gas-rich to gas-poor systems. No ISM was found in the least massive dwarfs.
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تاریخ انتشار 2001