## Abstract

We study the inner product of two Bethe states, one of which is taken on-shell, in an inhomogeneous XXX chain in the Sutherland limit, where the number of magnons is comparable with the length L of the chain and the magnon rapidities arrange in a small number of macroscopically large Bethe strings. The leading order in the large L limit is known to be expressed through a contour integral of a dilogarithm. Here we derive the sub-leading term. Our analysis is based on a new contour-integral representation of the inner product in terms of a Fredholm determinant. We give two derivations of the sub-leading term. Besides a direct derivation by solving a Riemann-Hilbert problem, we give a less rigorous, but more intuitive derivation by field-theoretical methods. For that we represent the Fredholm determinant as an expectation value in a Fock space of chiral fermions and then bosonize. We construct a collective field for the bosonized theory, the short wave-length part of which may be evaluated exactly, while the long wave-length part is amenable to a 1/L expansion. Our treatment thus results in a systematic 1/L expansion of structure factors within the Sutherland limit.

Original language | American English |
---|---|

Article number | 245401 |

Journal | Journal of Physics A: Mathematical and Theoretical |

Issue number | 24 |

DOIs | |

State | Published - 2014 |

### Bibliographical note

Publisher Copyright:© 2014 IOP Publishing Ltd.

## Keywords

- AdS/CFT
- Bethe Ansatz
- Slavnovs formula
- Sutherland limit
- Yang-Mills
- form factors
- integrability