Bridging the quartet and pair pictures of isovector proton-neutron pairing
Bridging the quartet and pair pictures of isovector proton-neutron pairing
The formal implications of a quartet coherent state ansatz for proton-neutron pairing are analyzed. Its nonlinear annihilation operators, which generalize the BCS linear quasiparticle operators, are computed in the quartetting case. Their structure is found to generate nontrivial relationships between the many body correlation functions. The intrinsic structure of the …