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The growth of dust particles into planet embryos needs to circumvent theradial-drift barrier, i.e. the accretion of dust particles onto the centralstar by radial migration. The outcome of the dust radial migration is governedby simple criteria between the dust-to-gas ratio and the exponents p and q ofthe surface density and temperature power laws. The transfer of radiationprovides an additional constraint between these quantities because the discthermal structure is fixed by the dust spatial distribution. To assess whichdiscs are primarily affected by the radial-drift barrier, we used the radiativetransfer code MCFOST to compute the temperature structure of a wide range ofdisc models, stressing the particular effects of grain size distributions andvertical settling.  We find that the outcome of the dust migration process is very sensitive tothe physical conditions within the disc. For high dust-to-gas ratios (> 0.01)or flattened disc structures (H/R < 0.05), growing dust grains can efficientlydecouple from the gas, leading to a high concentration of grains at a criticalradius of a few AU. Decoupling of grains can occur at a large fraction (> 0.1)of the initial radius, for a dust-to-gas ratio greater than ~ 0.05. The exactvalue of the required dust-to-gas ratio for dust to stop its migration isstrongly dependent on the disc temperature structure. Non growing dust grainsare accreted for discs with flat surface density profiles (p<0.7) while theyalways remain in the disc if the surface density is steep enough (p>1.2). Boththe presence of large grains and vertical settling tend to favour the accretionof non growing dust grains onto the central object, but it slows down themigration of growing dust grains. All the disc configurations are found to havefavourable temperature profiles over most of the disc to retain theirplanetesimals.

Diversity in the outcome of dust radial drift in protoplanetary discs