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CO J=2->1 observations of the nearby galaxies Dwingeloo 1 and Dwingeloo 2

R. P. J. Tilanus·W. B. Burton
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Abstract

We present an exploratory survey of the central regions of the nearby spiral galaxies Dwingeloo 1 and Dwingeloo 2 made in the CO J=2->1 line at 230GHz using the James Clerk Maxwell Telescope. In Dwingeloo 1, which is probably the nearest grand-design barred spiral, the CO emission was sampled along a cross with its major axis aligned with the bar. The CO emission is an order of magnitude weaker (peak Tmb=~70mK) than in its neighbours IC 342 and Maffei 2 and appears to be confined to the nucleus, bar, and spiral arms. In Dwingeloo 2, a small system quite likely to be a companion of Dw1, a 3-sigma upper limit of 40mK for the CO J=2->1 emission from the nucleus was obtained.

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R. P. J. Tilanus, W. B. Burton. 1997-09-30. CO J=2->1 observations of the nearby galaxies Dwingeloo 1 and Dwingeloo 2. https://arxiv.org/abs/astro-ph/9709306

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