The High-Velocity Clouds: Galactic or Intergalactic?
نویسندگان
چکیده
منابع مشابه
Highly Ionized High Velocity Clouds: Intergalactic Gas in the Local Group or Distant Gas in the Galactic Halo?
In the course of our studies of the gaseous halo surrounding the Milky Way, we have recently identified several high velocity (VLSR < -100 km s ) clouds in the directions of Mrk 509 and PKS 2155-304 that have unusual ionization properties. The clouds exhibit strong C IV absorption with little or no detectable low ion (C II, Si II) absorption or H I 21 cm emission down to very sensitive levels. ...
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From an analysis of the sky and velocity distributions of the high-velocity clouds (HVCs) we show that the majority of the HVCs has a common origin. We conclude that the HVCs surround the Galaxy, forming a metacloud of ∼ 300 kpc in size and with a mass of ∼ 3×109 M⊙, and that they are the product of a powerful “superwind” (about 10 58 ergs), which occurred in the Magellanic Clouds about 570 Myr...
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ژورنال
عنوان ژورنال: Symposium - International Astronomical Union
سال: 1999
ISSN: 0074-1809
DOI: 10.1017/s0074180900112252