CO Observations of Molecular Gas Around a Giant HII Region in M101.

Session 45 - Radio Astronomy, Yesterday, Today and Tomorrow.
Display session, Tuesday, June 11
Great Hall,

[45.01] CO Observations of Molecular Gas Around a Giant HII Region in M101.

J. Giannakopoulou, M. Fich (U. of Waterloo), C. D. Wilson (McMaster U.)

Using the James Clerk Maxwell Telescope, we observed two rotational transitions of CO (J=2\to1 and J=3\to2) toward NGC 5461---the brightest giant HII region in the M101 galaxy. With even higher resolution (a few arcseconds), we observed CO J=1\to0 in NGC 5461 using the Owens Valley Millimeter Array. The higher resolution observations resolve the peak seen in the J=2\to1 map to several smaller peaks. These giant molecular clouds have diameters up to 200 pc. Also, we have calculated the line ratio of ^12CO/^13CO to be between 6.7 and 8.1, which agrees well with the ratios found in M33. Finally, we obtained a marginal detection of ^13CO J=2\to1.

Program listing for Tuesday