The Ophiuchus Superbubble: A Gigantic Eruption from the Inner Disk of the Milky Way

Details The Ophiuchus Superbubble: A Gigantic Eruption from the Inner Disk of the Milky Way The Ophiuchus Superbubble: A Gigantic Eruption from the Inner Disk of the Milky Way

2006-10-30

arxiv.org/abs/astro-ph/0610894v1

Astrophys.J.656:928-942,2007

Astronomy and Astrophysics

Astrophysics

44 pages, 14 figures, accepted for publication in the Astrophysical Journal

Scientific paper

10.1086/510521

While studying extraplanar neutral hydrogen in the disk-halo transition of the inner Galaxy we have discovered what appears to be a huge superbubble centered around l ~ 30 deg, whose top extends to latitudes > 25 deg at a distance of about 7 kpc. It is detected in both HI and Halpha. Using the Green Bank Telescope of the NRAO, we have measured more than 220,000 HI spectra at 9' angular resolution in and around this structure. The total HI mass in the system is ~ 10^6 Msol and it has an equal mass in H+. The Plume of HI capping its top is 1.2 x 0.6 kpc in l and b and contains 3 x 10^4 Msol of HI. Despite its location, (the main section is 3.4 kpc above the Galactic plane) the kinematics of the Plume appears to be dominated by Galactic rotation, but with a lag of 27 km/s from corotation. At the base of this structure there are ``whiskers'' of HI several hundreds of pc wide, reaching more than 1 kpc into the halo; they have a vertical density structure suggesting that they are the bubble walls and have been created by sideways rather than upwards motion. They resemble the vertical dust lanes seen in NGC891. From a Kompaneets model of an expanding bubble, we estimate that the age of this system is ~ 30 Myr and its total energy content ~ 10^53 ergs. It may just now be at the stage where its expansion has ceased and the shell is beginning to undergo significant instabilities. This system offers an unprecedented opportunity to study a number of important phenomena at close range, including superbubble evolution, turbulence in an HI shell, and the magnitude of the ionizing flux above the Galactic disk.

Affiliated with

Also associated with

No associations

Rating

The Ophiuchus Superbubble: A Gigantic Eruption from the Inner Disk of the Milky Way 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 Ophiuchus Superbubble: A Gigantic Eruption from the Inner Disk of the Milky Way, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Ophiuchus Superbubble: A Gigantic Eruption from the Inner Disk of the Milky Way will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-229934