Astronomy and Astrophysics – Astronomy
Scientific paper
May 1994
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1994aas...184.2914l&link_type=abstract
American Astronomical Society, 184th AAS Meeting, #29.14; Bulletin of the American Astronomical Society, Vol. 26, p.903
Astronomy and Astrophysics
Astronomy
Scientific paper
We report the first direct measurement of the thermal pressure of the hot phase of the interstellar medium (ISM). This result is derived from the discovery of a shadow in the diffuse extreme ultraviolet background with the Extreme Ultraviolet Explorer (EUVE) Deep Survey telescope Lexan/boron filter (65--190 Angstroms). Variations in the diffuse EUV intensity observed along a 24-day scan of the ecliptic plane were found to be spatially anti-correlated with the IRAS 100 microns intensity of these regions. An individual absorption feature at l ~ 165, b ~ -32 was found to coincide with an isolated IRAS cirrus cloud, which though tenuous by usual standards, is optically thick at EUV wavelengths. The EUV intensity at the absorption feature yields the emission measure of the hot ISM in the line of sight to the cloud. The distance to the cloud has been found from optical work. These two results are combined to yield a direct determination of the thermal pressure. The value obtained is p/k =~ 19,000, which is almost a factor of seven larger than the most commonly assumed value. This work has been supported by NASA contract NAS5-30180.
Bowyer Stuart
Knude Jens
Lampton Michael
Lieu Richard
Sidher Sunil D.
No associations
LandOfFree
The First Direct Measurement of the Thermal Pressure of the Hot 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 The First Direct Measurement of the Thermal Pressure of the Hot Interstellar Medium, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The First Direct Measurement of the Thermal Pressure of the Hot Interstellar Medium will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-882388