Moment of inertia of a trapped superfluid gas of atomic fermions

The moment of inertia Θ of a trapped superfluid gas of atomic fermions ${(}^6\mathrm{Li})$ is calculated as a function of the temperature. At zero temperature the moment of inertia takes on the irrotational-flow value. Only for T very close to $T_c$ is rigid rotation attained. It is proposed that future measurements of the rotational energy will unambiguously reveal whether the system is in a superfluid state or not.