Description
New large-scale CO surveys of the first and second Galactic quadrants and the
nearby molecular cloud complexes in Orion and Taurus, obtained with the
Harvard-Smithsonian Center for Astrophysics 1.2 m telescope, have been
combined with 31 other surveys obtained over the past two decades with that
instrument and a similar telescope on Cerro Tololo in Chile, to produce a
new composite CO survey of the entire Milky Way. The survey consists of
488,000 spectra that Nyquist or beamwidth (1/8 deg) sample the entire Galactic
plane over a strip 4 deg-10 deg wide in latitude, and beamwidth or 1/4 deg sample
nearly all large local clouds at higher latitudes. Compared with the previous
composite CO survey of Dame et al. (1987), the new survey has 16 times more
spectra, up to 3.4 times higher angular resolution, and up to 10 times higher
sensitivity per unit solid angle.
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Users should be aware that both the angular resolution and the
sensitivity varies from region to region in the velocity-integrated map.
The component surveys were integrated individually using clipping or
moment masking in order to display nearly all statistically significant
emission but little noise above a level of ~1.5 K km/s. See the reference
below and the
<a href="http://cfa-www.harvard.edu/cfa/mmw/MilkyWayinMolClouds.html" >
Millimeter-Wave Group site</a> for more details
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