論文

査読有り
2017年8月

On the Disappearance of a Cold Molecular Torus around the Low-luminosity Active Galactic Nucleus of NGC 1097

ASTROPHYSICAL JOURNAL LETTERS
  • T. Izumi
  • K. Kohno
  • K. Fathi
  • E. Hatziminaoglou
  • R. I. Davies
  • S. Martin
  • S. Matsushita
  • E. Schinnerer
  • D. Espada
  • S. Aalto
  • K. Onishi
  • J. L. Turner
  • M. Imanishi
  • K. Nakanishi
  • D. S. Meier
  • K. Wada
  • N. Kawakatu
  • T. Nakajima
  • 全て表示

845
1
開始ページ
1-7
終了ページ
記述言語
英語
掲載種別
研究論文(学術雑誌)
DOI
10.3847/2041-8213/aa808f
出版者・発行元
IOP PUBLISHING LTD

We used the Atacama Large Millimeter/Submillimeter Array to map the CO(3-2) and the underlying continuum emissions around the type-1low-luminosity active galactic nucleus (LLAGN; bolometric luminosity less than or similar to 10(42) erg. s(-1)) of NGC 1097 at similar to 10 pc resolution. These observations revealed a detailed cold gas distribution within a similar to 100 pc of this LLAGN. In contrast to the luminous Seyfert galaxy NGC 1068, where a similar to 7 pc cold molecular torus was recently revealed, a distinctively dense and compact torus is missing in our CO(3-2) integrated intensity map of NGC 1097. Based on the CO(3-2) flux, the gas mass of the torus of NGC 1097 would be a factor of greater than or similar to 2-3 less than that found for NGC 1068 by using the same CO-to-H-2 conversion factor, which implies less active nuclear star formation and/or inflows in NGC 1097. Our dynamical modeling of the CO(3-2) velocity field implies that the cold molecular gas is concentrated in a thin layer as compared to the hot gas traced by the 2.12 mu m H-2 emission in and around the torus. Furthermore, we suggest that NGC 1097 hosts a geometrically thinner torus than NGC 1068. Although the physical origin of the torus thickness remains unclear, our observations support a theoretical prediction that geometrically thick tori with high opacity will become deficient as AGNs evolve from luminous Seyferts to LLAGNs.

リンク情報
DOI
https://doi.org/10.3847/2041-8213/aa808f
Web of Science
https://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=JSTA_CEL&SrcApp=J_Gate_JST&DestLinkType=FullRecord&KeyUT=WOS:000406926200005&DestApp=WOS_CPL
ID情報
  • DOI : 10.3847/2041-8213/aa808f
  • ISSN : 2041-8205
  • eISSN : 2041-8213
  • Web of Science ID : WOS:000406926200005

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