We investigate formation mechanisms for icy super-Earth-mass planets orbiting at 2-20?AU around 0.1-0.5?M ☉ stars. A large ensemble of coagulation calculations demonstrates a new formation channel: disks composed of large planetesimals with radii of 30-300?km form super-Earths on timescales of ~1?Gyr. In other gas-poor disks, a collisional cascade grinds planetesimals to dust before the largest planets reach super-Earth masses. Once icy Earth-mass planets form, they migrate through the leftover swarm of planetesimals at rates of 0.01-1?AU?Myr–1. On timescales of 10?Myr to 1?Gyr, many of these planets migrate through the disk of leftover planetesimals from semimajor axes of 5-10?AU to 1-2?AU. A few percent of super-Earths might migrate to semimajor axes of 0.1-0.2?AU. When the disk has an initial mass comparable with the minimum-mass solar nebula, scaled to the mass of the central star, the predicted frequency of super-Earths matches the observed frequency.
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