Discovery of Molecular and Atomic Clouds Associated with the Magellanic Superbubble 30 Doradus C
Abstract
We analyzed the 2.6 mm CO and 21 cm H I lines toward the Magellanic superbubble 30 Doradus C, in order to reveal the associated molecular and atomic gas. We uncovered five molecular clouds in a velocity range from 251 to 276 km s-1 toward the western shell. The non-thermal X-rays are clearly enhanced around the molecular clouds on a parsec scale, suggesting possible evidence for magnetic field amplification via shock-cloud interaction. The thermal X-rays are brighter in the eastern shell, where there are no dense molecular or atomic clouds, opposite to the western shell. The TeV γ-ray distribution may spatially match the total interstellar proton column density as well as the non-thermal X-rays. If the hadronic γ-ray is dominant, the total energy of the cosmic-ray protons is at least ∼ 1.2× {10}50 erg with the estimated mean interstellar proton density ∼60 cm-3. In addition, the γ-ray flux associated with the molecular cloud (e.g., MC3) could be detected and resolved by the Cherenkov Telescope Array (CTA). This should permit CTA to probe the diffusion of cosmic-rays into the associated dense ISM.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- July 2017
- DOI:
- 10.3847/1538-4357/aa73e0
- arXiv:
- arXiv:1701.01962
- Bibcode:
- 2017ApJ...843...61S
- Keywords:
-
- cosmic rays;
- gamma rays: ISM;
- ISM: bubbles;
- ISM: clouds;
- X-rays: individual: 30 Doradus C;
- Astrophysics - Astrophysics of Galaxies;
- Astrophysics - High Energy Astrophysical Phenomena
- E-Print:
- 9 pages, 5 figures, 1 table, accepted for publication in The Astrophysical Journal (ApJ)