Ambipolar diffusion and far-infrared polarization from the galactic circumnuclear disk

Steven Desch, W. G. Roberge

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

We describe an implicit prediction of the accretion disk models constructed by Wardle & Königl for the circumnuclear disk (CND) of gas and dust near the Galactic center: supersonic ambipolar diffusion, an essential dynamical ingredient of the Wardle-Königl disks, will cause the alignment of dust grains because of a process described by Roberge, Hanany, & Messinger. We calculate synthetic maps of the polarized thermal emission which would be caused by ambipolar alignment in the preferred Wardle-Königl model. Our maps are in reasonable agreement with 100 μm polarimetry of the CND if we assume that the grains have shapes similar to those of grains in nearby molecular clouds and that the CND contains a disordered magnetic field in energy equipartition with its ordered field.

Original languageEnglish (US)
JournalAstrophysical Journal
Volume475
Issue number2 PART II
StatePublished - 1997
Externally publishedYes

Fingerprint

ambipolar diffusion
polarization
dust
alignment
accretion
equipartition theorem
magnetic field
polarimetry
thermal emission
prediction
molecular clouds
gas
ingredients
accretion disks
energy
causes
predictions
gases
magnetic fields

Keywords

  • Dust, extinction
  • Galaxy: center
  • Infrared: ISM: continuum
  • ISM: magnetic fields
  • MHD
  • Polarization

ASJC Scopus subject areas

  • Space and Planetary Science

Cite this

Ambipolar diffusion and far-infrared polarization from the galactic circumnuclear disk. / Desch, Steven; Roberge, W. G.

In: Astrophysical Journal, Vol. 475, No. 2 PART II, 1997.

Research output: Contribution to journalArticle

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