SCUBA imaging of NGC 7331 dust ring

S. Bianchi; P. B. Alton; J. I. Davies; M. Trewhella

doi:10.1046/j.1365-8711.1998.01929.x

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arXiv · astro-ph/9806370

SCUBA imaging of NGC 7331 dust ring

S. Bianchi·P. B. Alton·J. I. Davies·M. Trewhella

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Abstract

We present observations of the spiral galaxy NGC 7331 using the Sub-millimetre Common User Bolometer Array (SCUBA) on the James Clark Maxwell Telescope. We have detected a dust ring of 45 arcsec radius (3.3 kpc) at wavelengths of 450 and 850-micron. The dust ring is in good correspondence with other observations of the ring in the mid-infrared (MIR), CO and radio-continuum, suggesting that the observed dust is associated with the molecular gas and star formation. A B-K colour map shows an analogous ring structure with an asymmetry about the major axis, consistent with the extinction being produced by a dust ring. The derived temperature of the dust lies between 16 and 31 K and the gas-to-dust ratio between 150 and 570, depending on the assumed dust emission efficiency index (beta=1.5 or 2.).

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S. Bianchi, P. B. Alton, J. I. Davies, M. Trewhella. 1998-06-29. SCUBA imaging of NGC 7331 dust ring. https://doi.org/10.1046/j.1365-8711.1998.01929.x

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