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arXiv · 2508.12449

Complex rational Ruijsenaars model. The two-particle case

N. M. Belousov·G. A. Sarkissian·V. P. Spiridonov
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Abstract

We consider a complex rational degeneration of the hyperbolic Ruijsenaars model emerging in the limit $\omega_1+\omega_2\to 0$ (or $b\to \imath$ in $2d$ CFT) and investigate in detail the two-particle case. Corresponding wave functions are described by complex hypergeometric functions in the Mellin-Barnes representation. Their dual integral representation and reflection symmetry in the coupling constant are established. Besides, a complex limit of the hyperbolic Baxter $Q$-operators is considered. Another complex degeneration of the hyperbolic Ruijsenaars model is obtained by taking a special $\omega_1-\omega_2\to 0$ (or $b\to 1$) limit. Additionally, two new degenerations to the complex Calogero-Sutherland type models are described.

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N. M. Belousov, G. A. Sarkissian, V. P. Spiridonov. 2025-08-17. Complex rational Ruijsenaars model. The two-particle case. https://doi.org/10.54546/naturalscirev.100503

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