Gravitational fragmentation and formation of giant protoplanets on orbits of tens of AU

Migration of dense gaseous clumps that form in young protostellar disks via gravitational fragmentation is investigated to determine the likelihood of giant-planet formation. We show that gaseous clumps that form in the outer regions of the disk (> 100 au) through disk fragmentation often migrate toward the central star on timescales from a few thousand to few tens of thousands of years. The tidal mass loss helps the clumps to significantly slow down or even halt their inward migration at a distance of a few tens of AU from the protostar.