NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
X-ray-emitting gas surrounding the spiral galaxy NGC 891We observed the edge-on spiral galaxy NGC 891 with the Position Sensitive Proportional Counter (PSPC) on Roentgen Satellite (ROSAT) to search for how extraplanar gas expected in the galactic fountain model. Diffuse X-ray emission surrounds the disk with a Half Width at Half Maximum (HWHM) for the surface brightness perpendicular to the disk of 50 sec (2.4 kpc) and a radial extent of approximately 6.5 kpc, both of which are similar in extent to the extended H(alpha) and radio halo component; the implied density scale height for the hot gas is 7 kpc. The spectrum is best fitted with a hard stellar component and a soft diffuse gas component of temperature 3.6 x 10(exp 6) K. The density of this gas is 2 x 10(exp -3)/cu cm, the luminosity is 4.4 x 10(exp 39) ergs/s, the mass is 1 x 10(exp 8) solar mass, and the pressure (P/k) is 1.4 10(exp 4) K/cu cm. These data are consistent with this gas participating in a galactic fountain, where the material approaches hydrostatic equilibrium before cooling at a rate of 0.12 solar mass/yr. The cooled material may be responsible for some of the H(alpha) emission.
Document ID
19950040028
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Bregman, Joel N.
(Univ. of Michigan, Ann Arbor, MI United States)
Pidis, Rachel A.
(Univ. of Michigan, Ann Arbor, MI United States)
Date Acquired
August 16, 2013
Publication Date
January 10, 1994
Publication Information
Publication: The Astrophysical Journal, Part 1
Volume: 420
Issue: 2
ISSN: 0004-637X
Subject Category
Astronomy
Accession Number
95A71627
Funding Number(s)
CONTRACT_GRANT: NAGW-2135
Distribution Limits
Public
Copyright
Other

Available Downloads

There are no available downloads for this record.
No Preview Available