Vortex momentum density and invariants of the hydrodynamic equations of superfluidity and superconductivity

The gauge transformation of the hydrodynamic equations of superfluidity and superconductivity is considered. The vortex and heat momentum densities are defined and their evolution equations are derived. The physical meaning of these quantities is analyzed. The Lagrangian invariants of the new set of equations, which are similar to those obtained by Hollman for classical hydrodynamics, are derived.