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Regge Spectral Generator and Form Factors from Hard Exclusive Amplitudes in Holographic QCD

Guy F. de Téramond1,*, Stanley J. Brodsky2,†, and Hans Günter Dosch3,‡

  • *Contact author: guy.deteramond@ucr.ac.cr
  • †Contact author: sjbth@slac.stanford.edu
  • ‡Contact author: h.g.dosch@gmail.com
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Phys. Rev. Lett. 137, 111903 – Published 9 September, 2026

DOI: https://doi.org/10.1103/55pw-29c6

Abstract

We show that the infinite tower of hard exclusive amplitudes in holographic light-front QCD leads to a spectral generator G(α,λ) that encodes the full Regge spectrum. The construction assumes a Poisson distribution of Fock-state components, where λ represents the average parton multiplicity above the valence configuration. The resulting generator yields a Regge spectrum invariant under continuous λ deformations. Its even- and odd-twist projections yield the meson and baryon form factors with a single value of λ, fixed by the pion charge radius, which in turn determines the full Q2 dependence. The constituent counting rules for both sectors follow from the structure of the spectral generator, which also provides a compact analytic representation of parton distributions.

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Phys. Rev. Lett. 137, 111903– Published 9 September, 2026
  • Received 29 March 2026
  • Revised 20 July 2026
  • Accepted 18 August 2026
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