  Highly excited states for isospin 1/2 baryons are calculated for the first
time using lattice QCD with two flavors of dynamical quarks. Anisotropic
lattices are used with two pion masses: 416(36) MeV and 578(29) MeV. The lowest
four energies are reported in each of the six irreducible representations of
the octahedral group at each pion mass. The lattices used have dimensions
24^3x64, spatial lattice spacing a_s = 0.11 fm and temporal lattice spacing a_t
= 1/3 a_s. Clear evidence is found for a 5/2^-state in the pattern of
negative-parity excited states. This agrees with the pattern of physical states
and spin 5/2 has been realized for the first time on the lattice.
