Probing The Kinematics Of Ionized Gas In The Galactic Center
Abstract
We have carried out radio recombination line (RRL) observations of the inner 2.0x0.5 (lxb) degrees of the Galactic center using the 100 m Green Bank Telescope. These measurements provided 0.9 km/s spectral resolution, 73" spatial resolution, and was sensitive to six RRLs (H86alpha - H91alpha) with the center transition at 9.17 GHz. An on-the-fly frequency-switched Nyquist sampled mapping scheme centered at l=359.95, b=-0.0473 was utilized. Here, we present preliminary results of this extensive survey of ionized gas with maps of the integrated intensity and details of various kinematical features. In particular, the kinematics of the diffuse Warm Ionized Medium as well as well-known massive star forming sites such as: Sgr A, Sgr B1 (G0.5-0.0), Sgr B2 (G0.7-0.0), Sgr C (G359.4-0.1), the sickle (G0.18-0.04), and the arched filaments of the radio arc near l 0.18 degrees are given. Highlights of this survey include the detection for the first time of various diffuse emission throughout the Galactic center. One such feature is an extensive large scale blueshifted structure from -80 to 0 km/s that appears to extend from Sgr C to the western ridge of the thermal arch at G0.07+0.04, a projected distance of 75 pc (30'). In addition, we find an extended broad ionized thermal component at 0 km/s near G0.15-0.18. This large-scale ridge of ionized gas runs between the linear nonthermal filaments and the Sgr A complex, mirroring the thermal arched filaments. The morphology of this structure appears to trace a wind-blown cavity roughly 13.5 pc in extent at G0.14-0.12.
- Publication:
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American Astronomical Society Meeting Abstracts #219
- Pub Date:
- January 2012
- Bibcode:
- 2012AAS...21925202R