Astronomy and Astrophysics – Astrophysics
Scientific paper
2000-10-10
Astronomy and Astrophysics
Astrophysics
This paper contains 31 pages of text and 23 figures. This paper was submitted to The Astrophysical Journal on 6/6/2000. It was
Scientific paper
10.1086/319057
This paper describes some interesting properties of waves in, and oscillations of, the interstellar medium in the direction normal to the plane of the Galaxy. Our purpose is to examine possible reasons for four observed phenomena: the falling sky in the northern hemisphere; the apparent presence of clouds in absorption spectra when a sightline is occupied primarily only by warm intercloud gas; the peculiar structuring of spiral arms involving clumps, spurs, and feathering; and the existence of an abundance of high stage ions far off the plane of the Galaxy. We explored the reaction of the interstellar medium - in the vertical direction only - to large imposed disturbances (initial displacements, expansive velocities, and compressions), and to the introduction of small amplitude waves via oscillation of the midplane. Our findings included: 1) the anticipated growth in amplitude of high frequency waves with height; 2) the four lowest normal modes for the oscillation of the atmosphere as a whole, as functions of the height of the outer boundary; 3) the time for material to `bounce' from one unusually dense state to the next as a function of height; and 4) the tendency for the disk to develop a hot outer halo, either after the passage of a single shock from a large event, or in response to a continuous stream of small amplitude waves.
Cox Donald P.
Walters Michael A.
No associations
LandOfFree
Models of Veritcal Disturbances in the Interstellar Medium does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Models of Veritcal Disturbances in the Interstellar Medium, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Models of Veritcal Disturbances in the Interstellar Medium will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-722592