Miquel Requena-Torres: Opening again the debate: the transient nature of the circumnuclear disk

Data from many sources
  • IRAM, APEX, Herschel
  • SOFIA now: FORCAST & GREAT
CO SED
  • Measure up to CO 21-20
  • Model with LVG
  • Needs multiple components
    • but no high-density components
HNC/HCO+
  • Mills et al, 2013... on arxiv tomorrow
  • Vibrationally excited H3CN
  • RADEX -> n~10^5.3-6.5
  • most of CND not tidally stable
  • High temperatures (120-150K) required to excite vibrationally excited gas
Many works indicate CND not stable
  • [Lacy indicated: doesn't need to be gravitationally stable; is formed by shear]
  • Betsy proposing HCN ladder with ALMA

Questions

  • Q: If densities below Roche densities, maybe clumps are not virialized but they contain virialized cores.
  • A: In very close...
  • Q: Model - black hole compresses clumps when they get closer to BH

Comments