Every solution of the Bethe-ansatz equations (BAEs) is characterized by a set of quantum
numbers, by which we can evaluate it numerically. However, no general rule is known how …

The exact solution of the eigenproblem of the Heisenberg Hamiltonian for the XXX model in
the case of a magnetic ring with N= 5 nodes is presented in a closed algebraic form. It is …

We analyse the exact solution of the eigenproblem for the Heisenberg Hamiltonian of
magnetic heptagon, ie the ring of N= 7 nodes, each with spin 1/2, within the XXX model with …

In this paper the field generated by the Bethe parameters related to the XXX model for the
Heisenberg pentagon is considered. For the interior of the Brillouin zone, the Galois group of …

The eigenproblem for the Heisenberg Hamiltonian for a ring of N nodes with the spin 1/2
and isotropic interaction, solved by the famous Bethe Ansatz, is reconsidered here for the …

We study the implications of the regularization for the singular solutions on the even (odd)
length spin-1/2 XXX chains in some specific down-spin sectors. In particular, the analytic …

We observe a different type of complex solutions in the isotropic spin-1/2 Heisenberg chain
starting from N= 12, where the central rapidity of some of the odd-length strings becomes …

The exact Bethe eigenfunctions for the heptagonal ring within the isotropic XXX model
exhibit a doubly degenerated energy level in the three-deviation sector at the centre of the …

We consider the factor υ of the characteristic polynomial w H (x) of the Heisenberg
Hamiltonian Ĥ of the XXX model, corresponding to the generic star [k=±1,±3] of …

Galois symmetry of exact Bethe Ansatz eigenstates for the magnetic pentagonal ring within
the XXX model are investigated by a comparison with crystallographic constructions of …