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arXiv · hep-th/0108071

Virial expansion and TBA in O(N) sigma models

J. Balog·A. Hegedus
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Abstract

We study the free energy of the 1+1 dimensional O(N) nonlinear sigma-models for even N using the TBA equations proposed recently. We give explicit formulae for the constant solution of the TBA equations (Y-system) and calculate the first two virial coefficients. The free energy is also compared to the leading large N result.

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J. Balog, A. Hegedus. 2001-08-10. Virial expansion and TBA in O(N) sigma models. https://doi.org/10.1016/s0370-2693(01)01307-7

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