Abstract
Radio continuum images and CO-line observations have been combined to study the relationship between molecular gas and the star formation rate within the disks of 180 spiral galaxies. We find a strong correlation between these two quantities. On average, the ratio between the radio continuum and the CO emission is constant (within a factor 3) both inside the same galaxy and from galaxy to galaxy. The star formation efficiency deduced from the radio continuum depends weakly on general galaxy properties. A comparison is made with another similar analysis performed using the H alpha luminosity as star formation indicator.
