Dense Ionized and Neutral Gas Surrounding Sgr A*

Details Dense Ionized and Neutral Gas Surrounding Sgr A* Dense Ionized and Neutral Gas Surrounding Sgr A*

2004-08-07

arxiv.org/abs/astro-ph/0408136v1

Astrophys.J. 616 (2004) 231-246

Astronomy and Astrophysics

Astrophysics

34 pages including 11 figures (4 jpgs), Latex, uses aastex. The full pdf format file including high resolution figures is avai

Scientific paper

10.1086/424868

We present high resolution H41a hydrogen recombination line observations of the 1.2' (3 pc) region surrounding Sgr A* at 92 GHz using the OVRO Millimeter Array with an angular resolution of 7" x 3" and velocity resolution of 13 km/s. New observations of H31a, H35a, H41a, and H44a lines were obtained using the NRAO 12-m telescope, and their relative line strengths are interpreted in terms of various emission mechanisms. These are the most extensive and most sensitive observations of recombination line to date. Observations of HCO+ (1 - 0) transition at 89 GHz are also obtained simultaneously with a 40% improved angular resolution and 4-15 times improved sensitivity over previous observations, and the distribution and kinematics of the dense molecular gas in the circumnuclear disk (CND) are mapped and compared with those of the ionized gas. The line brightness ratios of the hydrogen recombination lines are consistent with purely spontaneous emission from 7000 K gas with n_e = 20,000 cm$^{-3}$ near LTE condition. A virial analysis suggests that the most prominent molecular gas clumps in the CND have mean densities of 10^7 cm^{-3}, sufficient to withstand the tidal shear in the Galactic Center region. Therefore, these clumps may survive over several dynamical times, and the CND may be a dynamically stable structure. We estimate a total gas mass of 3 x 10^5 solar mass for the CND. \

Affiliated with

Also associated with

No associations

Rating

Dense Ionized and Neutral Gas Surrounding Sgr A* 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 Dense Ionized and Neutral Gas Surrounding Sgr A*, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Dense Ionized and Neutral Gas Surrounding Sgr A* will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-274403