Dusty Cradles in a Turbulent Nursery: The Sgr A East H II Complex at the Galactic Center

SOFIA/FORCAST images of the H II (ionized hydrogen) complex G0.02-0.07 resolved a string of three compact HII regions (labeled A, B, and C in Figure 1) plus two new infrared sources designated FIRS 1 and 2 (Figures 1 and 2). G0.02-0.07 is located in the Sagittarius A (Sgr A) region, 6 pc (20 light years) from our line of sight to the center of the Milky Way Galaxy. The Galactic Center includes a hot, turbulent interstellar medium, cloud-cloud collisions, stellar winds, and supernova shocks. This extreme environment provides a unique laboratory for testing models of star-formation processes.

The SOFIA/FORCAST data indicate that H II regions A, B, and C are heated and ionized by radiation from O stars, the most massive, luminous, and short-lived variety of normal stars. Region C likely contains more than one O star. The shape of region A plus motions of gas in and around it indicate a bow-shock interaction with a strong stellar wind. The source FIRS1 is probably a luminous protostar that is deeply embedded in a dense interstellar cloud. These observations are all consistent with characterization of G0.02-0.07 as a region of vigorous, ongoing massive star formation.

Detailed information can be found in Lau, Herter, Morris, & Adams 2014 (Astrophysical Journal 794, 108).

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