Generalized Gaudin systems in an external magnetic field and BCS-type

Description
We consider generalized Gaudin systems in an external magnetic field > corresponding to arbitrary sl(2)-valued non-skew-symmetric r-matrices > with spectral parameters and non-homogeneous external magnetic fields. > In the case of r-matrices diagonal in the sl(2) basis we calculate the > spectrum and the eigen-values of the corresponding generalized Gaudin > hamiltonians using the algebraic Bethe ansatz. We apply these results > to fermionic systems and obtain a wide class of integrable fermionic > BCS-type hamiltonians containing pairing and electrostatic interaction > terms. We consider important partial cases when the constructed > fermionic hamiltonian contains only pairing interaction term, i.e. is > an exact analogue of ``reduced" BCS hamiltonian of Richardson.
Organised by Luigi Amico