  The adiabatic self-consistent collective coordinate (ASCC) method is a
practical method for the description of large-amplitude collective motion in
atomic nuclei with superfluidity and an advanced version of the adiabatic
time-dependent Hartree-Fock-Bogoliubov theory. We investigate the gauge
symmetry in the ASCC method on the basis of the theory of constrained systems.
The gauge symmetry in the ASCC method is originated from the constraint on the
particle number in the collective Hamiltonian, and it is partially broken by
the adiabatic expansion. The validity of the adiabatic expansion under the
general gauge transformation is also discussed.
