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arXiv · hep-th/0307009

Thermodynamic Bethe ansatz for the AII sigma-models

Andrei Babichenko·Roberto Tateo
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Abstract

We derive thermodynamic Bethe ansatz equations describing the vacuum energy of the SU(2N)/Sp(N) nonlinear sigma model on a cylinder geometry. The starting points are the recently-proposed amplitudes for the scattering among the physical, massive excitations of the theory. The analysis fully confirms the correctness of the S-matrix. We also derive closed sets of functional relations for the pseudoenergies (Y-systems). These relations are shown to be the k-->infinity limit of the Sp(k+1)-related systems studied some years ago by Kuniba and Nakanishi in the framework of lattice models.

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Andrei Babichenko, Roberto Tateo. 2004-04-07. Thermodynamic Bethe ansatz for the AII sigma-models. https://doi.org/10.1016/j.physletb.2003.08.044

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