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Title: High velocity compact clouds in the sagittarius C region

We report the detection of extremely broad emission toward two molecular clumps in the Galactic central molecular zone. We have mapped the Sagittarius C complex (–0.°61 < l < –0.°27, –0.°29 < b < 0.°04) in the HCN J = 4-3, {sup 13}CO J = 3-2, and H{sup 13}CN J = 1-0 lines with the ASTE 10 m and NRO 45 m telescopes, detecting bright emission with 80-120 km s{sup –1} velocity width (in full-width at zero intensity) toward CO–0.30–0.07 and CO–0.40–0.22, which are high velocity compact clouds (HVCCs) identified with our previous CO J = 3-2 survey. Our data reveal an interesting internal structure of CO–0.30–0.07 comprising a pair of high velocity lobes. The spatial-velocity structure of CO–0.40–0.22 can be also understood as a multiple velocity component, or a velocity gradient across the cloud. They are both located on the rims of two molecular shells of about 10 pc in radius. Kinetic energies of CO–0.30–0.07 and CO–0.40–0.22 are (0.8-2) × 10{sup 49} erg and (1-4) × 10{sup 49} erg, respectively. We propose several interpretations of their broad emission: collision between clouds associated with the shells, bipolar outflow, expansion driven by supernovae (SNe), and rotation around a dark massive object.more » These scenarios cannot be discriminated because of the insufficient angular resolution of our data, though the absence of a visible energy source associated with the HVCCs seems to favor the cloud-cloud collision scenario. Kinetic energies of the two molecular shells are 1 × 10{sup 51} erg and 0.7 × 10{sup 51} erg, which can be furnished by multiple SN or hypernova explosions in 2 × 10{sup 5} yr. These shells are candidates of molecular superbubbles created after past active star formation.« less
Authors:
; ;  [1] ;  [2] ;  [3]
  1. Department of Physics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Yokohama, Kanagawa 223-8522 (Japan)
  2. Division of Physics, Faculty of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Ten-noudai, Tsukuba, Ibaraki 305-8571 (Japan)
  3. Department of Industrial Administration, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510 (Japan)
Publication Date:
OSTI Identifier:
22351344
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 783; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; C REGION; CARBON COMPLEXES; CARBON MONOXIDE; COLLISIONS; DETECTION; EMISSION; ENERGY SOURCES; EXPANSION; EXPLOSIONS; GALAXIES; RESOLUTION; RESONANCE IONIZATION MASS SPECTROSCOPY; SUPERNOVAE; TELESCOPES; VELOCITY