In this paper we presented a new high-sensitivity map of the continuum emission at 1.2 mm in the starburst galaxy M 82. To get a reliable map of the extended thermal dust emission we applied a CLEAN algorithm to our map (error beam correction) and subsequently subtracted the 12CO(2-1) line emission. Besides this the contribution of the sidelobes of the IRAM 30-m telescope has been estimated.
The total mass of dust in the inner 3 kpc of the galaxy derived from the integrated 1.2 mm flux density is , the inferred total mass of gas is .
Although the continuum emission is not confined to the galactic disk, our map rules out the existence of any pronounced halo of cold dust around M 82. We find the CO(2-1) line emission to be clearly more extended than the 1.2 mm dust emission. This unexpected observational result now waits for a conclusive theoretical explanation.
© European Southern Observatory (ESO) 2000
Online publication: June 26, 2000