COULOMB INTERACTIONS BETWEEN COSMIC-RAYS AND CHARGED DUST GRAINS

The transfer of kinetic energy between cosmic rays and charged dust gr ains is investigated. The time required for heating of the dust grains due to Coulomb interactions is estimated and compared with the heatin g time due to ionisation losses by the cosmic rays. Heating of dust gr ains by cosmic rays is examined in connection with the FIR-radio corre lation in galaxies: even for the most favorable conditions, including a high energy density in low-energy, less than or similar to 100 keV, cosmic rays, the conclusions are equivocal.