Astronomy and Astrophysics – Astrophysics – Galaxy Astrophysics
Scientific paper
2010-08-18
Astronomy and Astrophysics
Astrophysics
Galaxy Astrophysics
7 pages, 3 figures. To appear in "The Dynamic ISM: A celebration of the Canadian Galactic Plane Survey," ASP Conference Series
Scientific paper
The Galactic Arecibo L-band Feed Array HI (GALFA-HI) survey is mapping the entire Arecibo sky at 21-cm, over a velocity range of -700 to +700 km/s (LSR), at a velocity resolution of 0.18 km/s and an angular resolution of 3.5 arcmin. The unprecedented resolution and sensitivity of the GALFA-HI survey have resulted in the detection of many isolated, very compact HI clouds at low Galactic velocities which are distinctly separated from the HI disk emission. In the limited area of ~4600 deg$^2$ searched so far, we have detected 96 such compact clouds. The detected clouds are cold with kinetic temperature less than 300 K. Moreover, they are quite compact and faint, with median values of 5 arcmin in angular size, 0.75 K in peak brightness temperature, and $5\times10^{18}$ cm$^{-2}$ in HI column density. From the modeling of spatial and velocity distributions of the whole compact cloud population, we find that the bulk of clouds are related to the Galactic disk, and are within a few kpc distance. We present properties of the compact clouds sample and discuss various possible scenarios for the origin of this clouds population and its role in the Galactic interstellar medium studies.
Ballering Nicholas
Begum Ayesha
Douglas Kevin Arthur
Gallagher III S. . J.
Gibson Steven
No associations
LandOfFree
Galactic Small Scale Structure Revealed by the GALFA-HI Survey 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 Galactic Small Scale Structure Revealed by the GALFA-HI Survey, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Galactic Small Scale Structure Revealed by the GALFA-HI Survey will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-134402