We consider trends resulting from two formation mechanisms for short-periodsuper-Earths: planet-planet scattering and migration. We model scenarios wherethese planets originate near the snow line in ``cold finger'' circumstellardisks. Low-mass planet-planet scattering excites planets to low periastronorbits only for lower mass stars. With long circularisation times, theseplanets reside on long-period eccentric orbits. Closer formation regions meanplanets that reach short-period orbits by migration are most common aroundlow-mass stars. Above ~1 Solar mass, planets massive enough to migrate toclose-in orbits before the gas disk dissipates are above the critical mass forgas giant formation. Thus, there is an upper stellar mass limit forshort-period super-Earths that form by migration. If disk masses aredistributed as a power law, planet frequency increases with metallicity becausemost disks have low masses. For disk masses distributed around a relativelyhigh mass, planet frequency decreases with increasing metallicity. As icyplanets migrate, they shepherd interior objects toward the star, which grow to~1 Earth mass. In contrast to icy migrators, surviving shepherded planets arerocky. Upon reaching short-period orbits, planets are subject to evaporationprocesses. The closest planets may be reduced to rocky or icy cores. Low-massstars have lower EUV luminosities, so the level of evaporation decreases withdecreasing stellar mass.
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