  Integral field spectroscopy of galaxies at redshift z~2 has revealed a
population of early-forming, rotationally-supported disks. These high-redshift
systems provide a potentially important clue to the formation processes that
build disk galaxies in the universe. A particularly well-studied example is the
z=2.38 galaxy BzK-15504, which was shown by Genzel et al. (2006) to be a
rotationally supported disk despite the fact that its high star formation rate
and short gas consumption timescale require a very rapid acquisition of mass.
Previous kinematical analyses have suggested that z~2 disk galaxies like
BzK-15504 did not form through mergers because their line-of-sight velocity
fields display low levels of asymmetry. We perform the same kinematical
analysis on a set of simulated disk galaxies formed in gas-rich mergers of the
type that may be common at high redshift, and show that the remnant disks
display low velocity field asymmetry and satisfy the criteria that have been
used to classify high-redshift galaxies as disks observationally. Further, we
compare one of our remnants to the bulk properties of BzK-15504 and show that
it has a star formation rate, gas surface density, and a circular
velocity-to-velocity dispersion ratio that matches BzK-15504 remarkably well.
We suggest that observations of high-redshift disk galaxies like BzK-15504 are
consistent with the hypothesis that gas-rich mergers play an important role in
disk formation at high redshift.
