The specific shear viscosity ηˉ of a classically rotating system of
nucleons that interact via a monopole pairing interaction is calculated
including the effects of thermal fluctuations and coupling to pair vibrations
within the selfconsistent quasiparticle random-phase approximation. It is found
that ηˉ increases with angular momentum M at a given temperature T.
In medium and heavy systems, ηˉ decreases with increasing T at
T≥ 2 MeV and this feature is not affected much by angular momentum. But in
lighter systems (with the mass number A≤ 20), ηˉ increases with
T at a value of M close to the maximal value Mmax, which is defined as
the limiting angular momentum for each system. The values of ηˉ
obtained within the schematic model as well as for systems with realistic
single-particle energies are always larger than the universal lower-bound
conjecture ℏ/(4πkB) up to T=5 MeV.Comment: 19 pages, 7 figures, accepted for publication in Phys. Rev.