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Short-distance production of three particles with large scattering length

T. G. Backert1,*, S. Dietz1, H.-W. Hammer1,2,†, S. König1,3,‡, and D. T. Son4,§

  • *Contact author: timothy_george.backert@tu-darmstadt.de
  • †Contact author: hans-werner.hammer@physik.tu-darmstadt.de
  • ‡Contact author: skoenig@ncsu.edu
  • §Contact author: dtson@uchicago.edu
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Phys. Rev. C 113, 064001 – Published 18 June, 2026

DOI: https://doi.org/10.1103/lnzm-jzqt

Abstract

The short-distance production of multiparticle states in high-energy nuclear reactions provides a unique way to study the low-energy properties of few-body systems. In particular, the production amplitude of multineutron systems is strongly constrained by an approximate conformal symmetry of the underlying theory. We calculate the full amplitude for the short-distance production of three particles with large scattering length in leading-order pionless EFT, focusing on the cases of three neutrons and three spinless bosons. We investigate the signature of low-energy resonances and other correlations in the relative energy distributions. For the case of neutrons, we compare to the predictions from approximate conformal symmetry close to the unitary limit and calculate the range corrections up to next-to-next-to-leading order.

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Outline

Information

Phys. Rev. C 113, 064001– Published 18 June, 2026
  • Received 5 February 2026
  • Revised 23 March 2026
  • Accepted 23 April 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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