  Images of the Sun at millimeter wavelengths obtained by ALMA show a
significant correspondence with the magnetograms. In this paper, we investigate
this correspondence by comparing ALMA full-disk solar image taken at 1.2 mm
with a SDO/HMI magnetogram and analyze their correlation. It is found that
chromospheric network and active regions show a positive correlation where
brightness temperature is increasing with the line-of-sight magnetic field
strength, while sunspots have a negative correlation. Quiet Sun regions do not
show any dependence of the brightness temperature with the magnetic field.
Thermal bremsstrahlung is given as the best explanation for the observed
correlations.
