Journal of The Korean Astronomical Society (천문학회지)

The Korean Astronomical Society (한국천문학회)
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MECHANISM INDUCING GAS SUPPLY TO THE CENTRAL 10 PARSEC OF THE MILKY WAY

  • Morgan, Hannah L. (School of Space Research, Kyung Hee University) ;
  • Kim, Sungsoo S. (School of Space Research, Kyung Hee University) ;
  • Shin, Jihye (Korea Astronomy and Space Science Institute) ;
  • Chun, Kyungwon (School of Space Research, Kyung Hee University) ;
  • Park, So-Myoung (School of Space Research, Kyung Hee University) ;
  • Lee, Joowon (School of Space Research, Kyung Hee University) ;
  • Minh, Young Chol (Korea Astronomy and Space Science Institute)
  • Received : 2020.08.16
  • Accepted : 2020.11.03
  • Published : 2020.12.31
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Abstract

We investigate the plausibility of mass return, from stellar mass loss processes within the central ~100 pc region of the Milky Way (the inner nuclear bulge), as a mass supply mechanism for the Circumnuclear Disk (CND). Gas in the Galactic disk migrates inward to the Galactic centre due to the asymmetric potential caused by the Galactic bar. The inward migration of gas stops and accumulates to form the central molecular zone (CMZ), at 100-200 pc from the Galactic center. It is commonly assumed that stars have formed in the CMZ throughout the lifetime of the Galaxy and have diffused inward to form a 'r-2 stellar cusp' within the inner nuclear bulge. We propose that the stars migrating inward from the CMZ supply gas to the inner nuclear bulge via stellar mass loss, resulting in the formation of a gas disk along the Galactic plane and subsequent inward migration down to the central 10 pc region (CND). We simulate the evolution of a gas distribution that initially follows the stellar distribution of the aforementioned stellar cusp, and illustrate the potential gas supply toward the CND.

Keywords

Acknowledgement

We are grateful to the anonymous reviewers for their helpful suggestions.

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