  We herein develop a new simple model for giant planet formation, which
predicts the final mass of a giant planet born in a given disk, by adding the
disk mass loss due to photoevaporation and a new type II migration formula to
our previous model. The proposed model provides some interesting results.
First, it gives universal evolution tracks in the diagram of planetary mass and
orbital radius, which clarifies how giant planets migrate at growth in the
runaway gas accretion stage. Giant planets with a few Jupiter masses or less
suffer only a slight radial migration in the runaway gas accretion stage.
Second, the final mass of giant planets is approximately given as a function of
only three parameters: the initial disk mass at the starting time of runaway
gas accretion onto the planet, the mass loss rate due to photoevaporation, and
the starting time. On the other hand, the final planet mass is almost
independent of the disk radius, viscosity, and initial orbital radius. The
obtained final planet mass is similar to or less than 10% of the initial disk
mass. Third, the proposed model successfully explains properties in the mass
distribution of giant exoplanets with the mass distribution of observed
protoplanetary disks for a reasonable range of the mass loss rate due to
photoevaporation.
